#
#
(C) Copyright 2000 - 2004
# Wolfgang Denk, DENX Software Engineering,
wd@denx.de.
#
# See file CREDITS for list of people who contributed
to this
# project.
#
# This program is free software; you can
redistribute it and/or
# modify it under the terms of the GNU General
Public License as
# published by the Free Software Foundation; either
version 2 of
# the License, or (at your option) any later version.
#
#
This program is distributed in the hope that it will be useful,
# but
WITHOUT ANY WARRANTY; without even the implied warranty of
#
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more
details.
#
# You should have received a copy of the GNU General
Public License
# along with this program; if not, write to the Free
Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
# MA
02111-1307 USA
#
Summary:
========
This
directory contains the source code for U-Boot, a boot loader for
Embedded
boards based on PowerPC, ARM, MIPS and several other
processors, which can
be installed in a boot ROM and used to
initialize and test the hardware or
to download and run application
code.
The development of U-Boot
is closely related to Linux: some parts of
the source code originate in
the Linux source tree, we have some
header files in common, and special
provision has been made to
support booting of Linux images.
Some
attention has been paid to make this software easily
configurable and
extendable. For instance, all monitor commands are
implemented with the
same call interface, so that it's very easy to
add new commands. Also,
instead of permanently adding rarely used
code (for instance hardware test
utilities) to the monitor, you can
load and run it dynamically.
Status:
=======
In
general, all boards for which a configuration option exists in the
Makefile
have been tested to some extent and can be considered
"working".
In fact, many of them are used in production systems.
In case of
problems see the CHANGELOG and CREDITS files to find out
who contributed
the specific port.
Where to get help:
==================
In
case you have questions about, problems with or contributions for
U-Boot
you should send a message to the U-Boot mailing list at
<u-boot-users@lists.sourceforge.net>.
There is also an archive of
previous traffic on the mailing list - please
search the archive
before asking FAQ's. Please see
http://lists.sourceforge.net/lists/listinfo/u-boot-users/
Where
we come from:
===================
- start from 8xxrom
sources
- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
-
clean up code
- make it easier to add custom boards
- make it
possible to add other [PowerPC] CPUs
- extend functions, especially:
* Provide extended interface to Linux boot
loader
* S-Record download
* network boot
* PCMCIA / CompactFLash / ATA disk / SCSI
... boot
- create ARMBoot project
(http://sourceforge.net/projects/armboot)
- add other CPU families
(starting with ARM)
- create U-Boot project
(http://sourceforge.net/projects/u-boot)
Names and
Spelling:
===================
The "official" name of
this project is "Das U-Boot". The spelling
"U-Boot"
shall be used in all written text (documentation, comments
in source files
etc.). Example:
This is
the README file for the U-Boot project.
File names etc. shall be
based on the string "u-boot". Examples:
include/asm-ppc/u-boot.h
#include <asm/u-boot.h>
Variable
names, preprocessor constants etc. shall be either based on
the string
"u_boot" or on "U_BOOT". Example:
U_BOOT_VERSION u_boot_logo
IH_OS_U_BOOT u_boot_hush_start
Versioning:
===========
U-Boot
uses a 3 level version number containing a version, a
sub-version, and a
patchlevel: "U-Boot-2.34.5" means version "2",
sub-version
"34", and patchlevel "4".
The patchlevel is used
to indicate certain stages of development
between released versions, i. e.
officially released versions of
U-Boot will always have a patchlevel of
"0".
Directory Hierarchy:
====================
-
board Board dependent
files
- common Misc architecture
independent functions
- cpu CPU
specific files
- 74xx_7xx Files specific to Freescale MPC74xx and
7xx CPUs
- arm720t Files specific to ARM 720 CPUs
- arm920t Files
specific to ARM 920 CPUs
- imx Files specific to Freescale MC9328 i.MX
CPUs
- s3c24x0 Files specific to Samsung S3C24X0
CPUs
- arm925t Files specific to ARM 925 CPUs
- arm926ejs Files
specific to ARM 926 CPUs
-
arm1136 Files specific to ARM 1136
CPUs
- at91rm9200 Files specific to Atmel AT91RM9200
CPUs
- i386 Files specific to i386 CPUs
- ixp Files
specific to Intel XScale IXP CPUs
- mcf52x2 Files specific to
Freescale ColdFire MCF52x2 CPUs
-
mips Files specific to MIPS CPUs
- mpc5xx Files
specific to Freescale MPC5xx CPUs
- mpc5xxx Files
specific to Freescale MPC5xxx CPUs
- mpc8xx Files specific to
Freescale MPC8xx CPUs
- mpc8220 Files
specific to Freescale MPC8220 CPUs
- mpc824x Files specific to
Freescale MPC824x CPUs
- mpc8260 Files specific to Freescale MPC8260 CPUs
- mpc85xx Files
specific to Freescale MPC85xx CPUs
- nios Files specific to Altera NIOS CPUs
- nios2 Files
specific to Altera Nios-II CPUs
-
ppc4xx Files specific to IBM PowerPC 4xx
CPUs
- pxa Files specific to Intel XScale PXA CPUs
- s3c44b0 Files
specific to Samsung S3C44B0 CPUs
- sa1100 Files specific to Intel
StrongARM SA1100 CPUs
- disk Code
for disk drive partition handling
- doc Documentation
(don't expect too much)
- drivers Commonly
used device drivers
- dtt Digital
Thermometer and Thermostat drivers
- examples Example code for standalone applications, etc.
- include Header Files
- lib_arm Files generic to ARM architecture
- lib_generic Files
generic to all architectures
-
lib_i386 Files generic to i386 architecture
- lib_m68k Files generic to m68k architecture
- lib_mips Files
generic to MIPS architecture
-
lib_nios Files generic to NIOS architecture
- lib_ppc Files generic to PowerPC architecture
-
net Networking code
- post Power On Self Test
- rtc Real Time Clock drivers
- tools Tools to build S-Record or U-Boot
images, etc.
Software Configuration:
=======================
Configuration
is usually done using C preprocessor defines; the
rationale behind that is
to avoid dead code whenever possible.
There are two classes of
configuration variables:
* Configuration _OPTIONS_:
These are selectable by the user and have
names beginning with
"CONFIG_".
* Configuration _SETTINGS_:
These depend on the hardware etc. and should
not be meddled with if
you don't
know what you're doing; they have names beginning with
"CFG_".
Later we will
add a configuration tool - probably similar to or even
identical to what's
used for the Linux kernel. Right now, we have to
do the configuration by
hand, which means creating some symbolic
links and editing some
configuration files. We use the TQM8xxL boards
as an example here.
Selection
of Processor Architecture and Board Type:
---------------------------------------------------
For
all supported boards there are ready-to-use default
configurations
available; just type "make <board_name>_config".
Example:
For a TQM823L module type:
cd
u-boot
make
TQM823L_config
For the Cogent platform, you need to specify the cpu
type as well;
e.g. "make cogent_mpc8xx_config". And also
configure the cogent
directory according to the instructions in cogent/README.
Configuration
Options:
----------------------
Configuration depends on the
combination of board and CPU type; all
such information is kept in a
configuration file
"include/configs/<board_name>.h".
Example:
For a TQM823L module, all configuration settings are in
"include/configs/TQM823L.h".
Many
of the options are named exactly as the corresponding Linux
kernel
configuration options. The intention is to make it easier to
build a
config tool - later.
The following options need to be configured:
-
CPU Type: Define exactly one of
PowerPC based CPUs:
-------------------
CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
or CONFIG_MPC5xx
or CONFIG_MPC8220
or CONFIG_MPC824X,
CONFIG_MPC8260
or CONFIG_MPC85xx
or CONFIG_IOP480
or CONFIG_405GP
or CONFIG_405EP
or CONFIG_440
or CONFIG_MPC74xx
or CONFIG_750FX
ARM based CPUs:
---------------
CONFIG_SA1110
CONFIG_ARM7
CONFIG_PXA250
MicroBlaze based CPUs:
----------------------
CONFIG_MICROBLAZE
Nios-2 based CPUs:
----------------------
CONFIG_NIOS2
-
Board Type: Define exactly one
of
PowerPC based
boards:
---------------------
CONFIG_ADCIOP CONFIG_GEN860T CONFIG_PCI405
CONFIG_ADS860 CONFIG_GENIETV CONFIG_PCIPPC2
CONFIG_AMX860 CONFIG_GTH CONFIG_PCIPPC6
CONFIG_AR405 CONFIG_gw8260 CONFIG_pcu_e
CONFIG_BAB7xx CONFIG_hermes CONFIG_PIP405
CONFIG_c2mon CONFIG_hymod CONFIG_PM826
CONFIG_CANBT CONFIG_IAD210 CONFIG_ppmc8260
CONFIG_CCM CONFIG_ICU862 CONFIG_QS823
CONFIG_CMI CONFIG_IP860 CONFIG_QS850
CONFIG_cogent_mpc8260 CONFIG_IPHASE4539 CONFIG_QS860T
CONFIG_cogent_mpc8xx CONFIG_IVML24 CONFIG_RBC823
CONFIG_CPCI405 CONFIG_IVML24_128 CONFIG_RPXClassic
CONFIG_CPCI4052 CONFIG_IVML24_256 CONFIG_RPXlite
CONFIG_CPCIISER4 CONFIG_IVMS8 CONFIG_RPXsuper
CONFIG_CPU86 CONFIG_IVMS8_128 CONFIG_rsdproto
CONFIG_CRAYL1 CONFIG_IVMS8_256 CONFIG_sacsng
CONFIG_CSB272 CONFIG_JSE CONFIG_Sandpoint8240
CONFIG_CU824 CONFIG_LANTEC CONFIG_Sandpoint8245
CONFIG_DASA_SIM CONFIG_lwmon CONFIG_sbc8260
CONFIG_DB64360 CONFIG_MBX CONFIG_sbc8560
CONFIG_DB64460 CONFIG_MBX860T CONFIG_SM850
CONFIG_DU405 CONFIG_MHPC CONFIG_SPD823TS
CONFIG_DUET_ADS CONFIG_MIP405 CONFIG_STXGP3
CONFIG_EBONY CONFIG_MOUSSE CONFIG_SXNI855T
CONFIG_ELPPC CONFIG_MPC8260ADS CONFIG_TQM823L
CONFIG_ELPT860 CONFIG_MPC8540ADS CONFIG_TQM8260
CONFIG_ep8260 CONFIG_MPC8560ADS CONFIG_TQM850L
CONFIG_ERIC CONFIG_MUSENKI CONFIG_TQM855L
CONFIG_ESTEEM192E CONFIG_MVS1 CONFIG_TQM860L
CONFIG_ETX094 CONFIG_NETPHONE CONFIG_TTTech
CONFIG_EVB64260 CONFIG_NETTA CONFIG_UTX8245
CONFIG_FADS823 CONFIG_NETVIA CONFIG_V37
CONFIG_FADS850SAR CONFIG_NX823 CONFIG_W7OLMC
CONFIG_FADS860T CONFIG_OCRTC CONFIG_W7OLMG
CONFIG_FLAGADM CONFIG_ORSG CONFIG_WALNUT405
CONFIG_FPS850L CONFIG_OXC CONFIG_ZPC1900
CONFIG_FPS860L CONFIG_ZUMA
ARM based boards:
-----------------
CONFIG_AT91RM9200DK, CONFIG_CERF250, CONFIG_DNP1110,
CONFIG_EP7312, CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE,
CONFIG_IMPA7, CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610,
CONFIG_LART, CONFIG_LPD7A400 CONFIG_LUBBOCK,
CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4, CONFIG_SHANNON,
CONFIG_P2_OMAP730, CONFIG_SMDK2400, CONFIG_SMDK2410,
CONFIG_TRAB, CONFIG_VCMA9
MicroBlaze based boards:
------------------------
CONFIG_SUZAKU
Nios-2 based boards:
------------------------
CONFIG_PCI5441 CONFIG_PK1C20
-
CPU Module Type: (if CONFIG_COGENT is defined)
Define exactly one of
CONFIG_CMA286_60_OLD
--- FIXME --- not tested
yet:
CONFIG_CMA286_60,
CONFIG_CMA286_21, CONFIG_CMA286_60P,
CONFIG_CMA287_23,
CONFIG_CMA287_50
- Motherboard Type: (if CONFIG_COGENT is
defined)
Define exactly
one of
CONFIG_CMA101,
CONFIG_CMA102
- Motherboard I/O Modules: (if CONFIG_COGENT is
defined)
Define one or
more of
CONFIG_CMA302
-
Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
Define one or more of
CONFIG_LCD_HEARTBEAT - update a character position on
the lcd display every second with
a "rotator" |\-/|\-/
-
Board flavour: (if CONFIG_MPC8260ADS is defined)
CONFIG_ADSTYPE
Possible
values are:
CFG_8260ADS - original MPC8260ADS
CFG_8266ADS - MPC8266ADS
CFG_PQ2FADS -
PQ2FADS-ZU or PQ2FADS-VR
CFG_8272ADS - MPC8272ADS
- MPC824X Family Member
(if CONFIG_MPC824X is defined)
Define
exactly one of
CONFIG_MPC8240,
CONFIG_MPC8245
- 8xx CPU Options: (if using an MPC8xx cpu)
CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
get_gclk_freq() cannot work
e.g. if there is no 32KHz
reference PIT/RTC clock
CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
or XTAL/EXTAL)
- 859/866/885 CPU
options: (if using a MPC859 or MPC866 or MPC885 CPU):
CFG_8xx_CPUCLK_MIN
CFG_8xx_CPUCLK_MAX
CONFIG_8xx_CPUCLK_DEFAULT
See doc/README.MPC866
CFG_MEASURE_CPUCLK
Define this to measure the actual
CPU clock instead
of
relying on the correctness of the configured
values. Mostly useful for board bringup to make
sure
the PLL is locked at
the intended frequency. Note
that
this requires a (stable) reference clock (32 kHz
RTC clock or CFG_8XX_XIN)
- Linux Kernel
Interface:
CONFIG_CLOCKS_IN_MHZ
U-Boot stores all clock information
in Hz
internally. For
binary compatibility with older Linux
kernels
(which expect the clocks passed in the
bd_info
data to be in MHz) the environment variable
"clocks_in_mhz" can be defined so that
U-Boot
converts clock
data to MHZ before passing it to the
Linux
kernel.
When
CONFIG_CLOCKS_IN_MHZ is defined, a definition of
"clocks_in_mhz=1" is automatically
included in the
default
environment.
CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
When transfering memsize parameter
to linux, some versions
expect
it to be in bytes, others in MB.
Define
CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
- Serial Ports:
CFG_PL010_SERIAL
Define this if you want support for
Amba PrimeCell PL010 UARTs.
CFG_PL011_SERIAL
Define this if you want support for
Amba PrimeCell PL011 UARTs.
CONFIG_PL011_CLOCK
If you have Amba PrimeCell PL011
UARTs, set this variable to
the
clock speed of the UARTs.
CONFIG_PL01x_PORTS
If you have Amba PrimeCell PL010 or
PL011 UARTs on your board,
define
this to a list of base addresses for each (supported)
port. See e.g.
include/configs/versatile.h
- Console Interface:
Depending on board, define exactly
one serial port
(like
CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
CONFIG_8xx_CONS_SCC1, ...), or switch off the
serial
console by
defining CONFIG_8xx_CONS_NONE
Note:
if CONFIG_8xx_CONS_NONE is defined, the serial
port routines must be defined elsewhere
(i.e. serial_init(), serial_getc(),
...)
CONFIG_CFB_CONSOLE
Enables console device for a color
framebuffer. Needs following
defines
(cf. smiLynxEM, i8042, board/eltec/bab7xx)
VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
(default
big endian)
VIDEO_HW_RECTFILL graphic chip supports
rectangle
fill
(cf.
smiLynxEM)
VIDEO_HW_BITBLT graphic chip supports
bit-blit
(cf. smiLynxEM)
VIDEO_VISIBLE_COLS visible pixel columns
(cols=pitch)
VIDEO_VISIBLE_ROWS visible pixel rows
VIDEO_PIXEL_SIZE bytes per pixel
VIDEO_DATA_FORMAT graphic
data format
(0-5,
cf. cfb_console.c)
VIDEO_FB_ADRS framebuffer address
VIDEO_KBD_INIT_FCT keyboard int fct
(i.e.
i8042_kbd_init())
VIDEO_TSTC_FCT test char fct
(i.e.
i8042_tstc)
VIDEO_GETC_FCT get char fct
(i.e.
i8042_getc)
CONFIG_CONSOLE_CURSOR cursor drawing on/off
(requires
blink timer
cf.
i8042.c)
CFG_CONSOLE_BLINK_COUNT
blink interval (cf. i8042.c)
CONFIG_CONSOLE_TIME display time/date info in
upper right
corner
(requires
CFG_CMD_DATE)
CONFIG_VIDEO_LOGO display Linux logo in
upper left
corner
CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
linux_logo.h
for logo.
Requires
CONFIG_VIDEO_LOGO
CONFIG_CONSOLE_EXTRA_INFO
addional
board info beside
the
logo
When
CONFIG_CFB_CONSOLE is defined, video console is
default i/o. Serial console can be forced with
environment 'console=serial'.
When CONFIG_SILENT_CONSOLE is
defined, all console
messages
(by U-Boot and Linux!) can be silenced with
the "silent" environment variable. See
doc/README.silent for more
information.
- Console Baudrate:
CONFIG_BAUDRATE - in bps
Select one of the baudrates listed in
CFG_BAUDRATE_TABLE, see below.
CFG_BRGCLK_PRESCALE, baudrate
prescale
- Interrupt driven serial port input:
CONFIG_SERIAL_SOFTWARE_FIFO
PPC405GP only.
Use an interrupt handler for
receiving data on the
serial
port. It also enables using hardware handshake
(RTS/CTS) and UART's built-in FIFO. Set the number
of
bytes the interrupt
driven input buffer should have.
Leave
undefined to disable this feature, including
disable the buffer and hardware handshake.
-
Console UART Number:
CONFIG_UART1_CONSOLE
IBM PPC4xx only.
If defined internal UART1 (and not
UART0) is used
as default
U-Boot console.
- Boot Delay: CONFIG_BOOTDELAY
- in seconds
Delay before
automatically booting the default image;
set
to -1 to disable autoboot.
See
doc/README.autoboot for these options that
work with CONFIG_BOOTDELAY. None are required.
CONFIG_BOOT_RETRY_TIME
CONFIG_BOOT_RETRY_MIN
CONFIG_AUTOBOOT_KEYED
CONFIG_AUTOBOOT_PROMPT
CONFIG_AUTOBOOT_DELAY_STR
CONFIG_AUTOBOOT_STOP_STR
CONFIG_AUTOBOOT_DELAY_STR2
CONFIG_AUTOBOOT_STOP_STR2
CONFIG_ZERO_BOOTDELAY_CHECK
CONFIG_RESET_TO_RETRY
-
Autoboot Command:
CONFIG_BOOTCOMMAND
Only needed when CONFIG_BOOTDELAY is
enabled;
define a command
string that is automatically executed
when
no character is read on the console interface
within "Boot Delay" after reset.
CONFIG_BOOTARGS
This can be used to pass arguments
to the bootm
command. The
value of CONFIG_BOOTARGS goes into the
environment
value "bootargs".
CONFIG_RAMBOOT
and CONFIG_NFSBOOT
The
value of these goes into the environment as
"ramboot" and "nfsboot" respectively,
and can be used
as a
convenience, when switching between booting from
ram and nfs.
- Pre-Boot Commands:
CONFIG_PREBOOT
When this option is #defined, the
existence of the
environment
variable "preboot" will be checked
immediately before starting the CONFIG_BOOTDELAY
countdown and/or running the
auto-boot command resp.
entering
interactive mode.
This
feature is especially useful when "preboot" is
automatically generated or modified.
For an example
see the
LWMON board specific code: here "preboot" is
modified when the user holds down a
certain
combination of
keys on the (special) keyboard when
booting
the systems
- Serial Download Echo Mode:
CONFIG_LOADS_ECHO
If defined to 1, all characters
received during a
serial
download (using the "loads" command) are
echoed back. This might be needed by some terminal
emulations (like "cu"),
but may as well just take
time
on others. This setting #define's the initial
value of the "loads_echo" environment
variable.
- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
CONFIG_KGDB_BAUDRATE
Select one of the baudrates listed
in
CFG_BAUDRATE_TABLE,
see below.
- Monitor Functions:
CONFIG_COMMANDS
Most
monitor functions can be selected (or
de-selected)
by adjusting the definition of
CONFIG_COMMANDS;
to select individual functions,
#define
CONFIG_COMMANDS by "OR"ing any of the
following values:
#define enables commands:
-------------------------
CFG_CMD_ASKENV *
ask for env variable
CFG_CMD_AUTOSCRIPT
Autoscript Support
CFG_CMD_BDI
bdinfo
CFG_CMD_BEDBUG * Include BedBug Debugger
CFG_CMD_BMP * BMP support
CFG_CMD_BSP * Board specific commands
CFG_CMD_BOOTD bootd
CFG_CMD_CACHE * icache, dcache
CFG_CMD_CONSOLE
coninfo
CFG_CMD_DATE * support for RTC, date/time...
CFG_CMD_DHCP * DHCP support
CFG_CMD_DIAG * Diagnostics
CFG_CMD_DOC *
Disk-On-Chip Support
CFG_CMD_DTT * Digital Therm and Thermostat
CFG_CMD_ECHO * echo arguments
CFG_CMD_EEPROM * EEPROM read/write support
CFG_CMD_ELF * bootelf, bootvx
CFG_CMD_ENV
saveenv
CFG_CMD_FDC * Floppy Disk Support
CFG_CMD_FAT * FAT partition support
CFG_CMD_FDOS * Dos diskette Support
CFG_CMD_FLASH flinfo, erase,
protect
CFG_CMD_FPGA
FPGA device initialization support
CFG_CMD_HWFLOW * RTS/CTS hw flow control
CFG_CMD_I2C * I2C serial bus support
CFG_CMD_IDE * IDE harddisk support
CFG_CMD_IMI iminfo
CFG_CMD_IMLS List all found
images
CFG_CMD_IMMAP * IMMR dump support
CFG_CMD_IRQ * irqinfo
CFG_CMD_ITEST
Integer/string test of 2 values
CFG_CMD_JFFS2 * JFFS2 Support
CFG_CMD_KGDB * kgdb
CFG_CMD_LOADB
loadb
CFG_CMD_LOADS
loads
CFG_CMD_MEMORY md,
mm, nm, mw, cp, cmp, crc, base,
loop, loopw, mtest
CFG_CMD_MISC Misc functions like
sleep etc
CFG_CMD_MMC * MMC memory mapped support
CFG_CMD_MII * MII utility commands
CFG_CMD_NAND * NAND support
CFG_CMD_NET bootp, tftpboot,
rarpboot
CFG_CMD_PCI * pciinfo
CFG_CMD_PCMCIA * PCMCIA support
CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
CFG_CMD_PORTIO * Port I/O
CFG_CMD_REGINFO * Register dump
CFG_CMD_RUN run command in env
variable
CFG_CMD_SAVES * save S record dump
CFG_CMD_SCSI * SCSI Support
CFG_CMD_SDRAM * print SDRAM configuration
information
CFG_CMD_SETGETDCR
Support for DCR Register access (4xx only)
CFG_CMD_SPI * SPI
serial bus support
CFG_CMD_USB * USB support
CFG_CMD_VFD * VFD
support (TRAB)
CFG_CMD_BSP * Board SPecific functions
CFG_CMD_CDP * Cisco Discover Protocol support
-----------------------------------------------
CFG_CMD_ALL all
CONFIG_CMD_DFL Default configuration; at the moment
this is includes all
commands, except
the
ones marked with "*" in the list
above.
If you don't define CONFIG_COMMANDS it defaults to
CONFIG_CMD_DFL in
include/cmd_confdefs.h. A board can
override the default settings in the
respective
include
file.
EXAMPLE: If
you want all functions except of network
support
you can write:
#define
CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
Note: Don't
enable the "icache" and "dcache" commands
(configuration option CFG_CMD_CACHE)
unless you know
what you
(and your U-Boot users) are doing. Data
cache
cannot be enabled on systems like the 8xx or
8260 (where accesses to the IMMR region must be
uncached), and it cannot be disabled
on all other
systems
where we (mis-) use the data cache to hold an
initial stack and some data.
XXX - this list needs to get
updated!
- Watchdog:
CONFIG_WATCHDOG
If this variable is defined, it
enables watchdog
support.
There must be support in the platform specific
code for a watchdog. For the 8xx and 8260 CPUs, the
SIU Watchdog feature is enabled in
the SYPCR
register.
-
U-Boot Version:
CONFIG_VERSION_VARIABLE
If this variable is defined, an
environment variable
named
"ver" is created by U-Boot showing the U-Boot
version as printed by the
"version" command.
This
variable is readonly.
- Real-Time Clock:
When CFG_CMD_DATE is selected, the
type of the RTC
has to be
selected, too. Define exactly one of the
following
options:
CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
CONFIG_RTC_MC146818 - use MC146818 RTC
CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
CONFIG_RTC_DS164x - use Dallas DS164x RTC
CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Note that if the RTC uses I2C, then
the I2C interface
must
also be configured. See I2C Support, below.
- Timestamp
Support:
When CONFIG_TIMESTAMP is selected, the
timestamp
(date and time)
of an image is printed by image
commands
like bootm or iminfo. This option is
automatically
enabled when you select CFG_CMD_DATE .
- Partition Support:
CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
and/or CONFIG_ISO_PARTITION
If IDE or SCSI support is
enabled (CFG_CMD_IDE or
CFG_CMD_SCSI)
you must configure support for at least
one
partition type as well.
- IDE Reset method:
CONFIG_IDE_RESET_ROUTINE - this is
defined in several
board
configurations files but used nowhere!
CONFIG_IDE_RESET - is this is defined, IDE Reset
will
be performed by
calling the function
ide_set_reset(int
reset)
which has to be
defined in a board specific file
- ATAPI Support:
CONFIG_ATAPI
Set this to enable ATAPI
support.
- LBA48 Support
CONFIG_LBA48
Set this to enable support for disks
larger than 137GB
Also
look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
Whithout these , LBA48 support uses
32bit variables and will 'only'
support
disks up to 2.1TB.
CFG_64BIT_LBA:
When enabled, makes the IDE
subsystem use 64bit sector addresses.
Default
is 32bit.
- SCSI Support:
At
the moment only there is only support for the
SYM53C8XX SCSI controller; define
CONFIG_SCSI_SYM53C8XX to enable
it.
CFG_SCSI_MAX_LUN
[8], CFG_SCSI_MAX_SCSI_ID [7] and
CFG_SCSI_MAX_DEVICE
[CFG_SCSI_MAX_SCSI_ID *
CFG_SCSI_MAX_LUN]
can be adjusted to define the
maximum
numbers of LUNs, SCSI ID's and target
devices.
CFG_SCSI_SYM53C8XX_CCF to fix clock
timing (80Mhz)
- NETWORK Support (PCI):
CONFIG_E1000
Support
for Intel 8254x gigabit chips.
CONFIG_EEPRO100
Support for Intel
82557/82559/82559ER chips.
Optional
CONFIG_EEPRO100_SROM_WRITE enables eeprom
write
routine for first time initialisation.
CONFIG_TULIP
Support
for Digital 2114x chips.
Optional
CONFIG_TULIP_SELECT_MEDIA for board specific
modem chip initialisation (KS8761/QS6611).
CONFIG_NATSEMI
Support for National dp83815
chips.
CONFIG_NS8382X
Support for National dp8382[01]
gigabit chips.
- NETWORK Support (other):
CONFIG_DRIVER_LAN91C96
Support for SMSC's LAN91C96
chips.
CONFIG_LAN91C96_BASE
Define this to hold the
physical address
of
the LAN91C96's I/O space
CONFIG_LAN91C96_USE_32_BIT
Define this to enable 32 bit
addressing
CONFIG_DRIVER_SMC91111
Support for SMSC's LAN91C111
chip
CONFIG_SMC91111_BASE
Define this to hold the
physical address
of
the device (I/O space)
CONFIG_SMC_USE_32_BIT
Define this if data bus is 32
bits
CONFIG_SMC_USE_IOFUNCS
Define this to use i/o
functions instead of macros
(some
hardware wont work with macros)
- USB Support:
At the moment only the UHCI host
controller is
supported
(PIP405, MIP405, MPC5200); define
CONFIG_USB_UHCI
to enable it.
define
CONFIG_USB_KEYBOARD to enable the USB Keyboard
and define CONFIG_USB_STORAGE to enable the USB
storage devices.
Note:
Supported are USB Keyboards and USB Floppy drives
(TEAC FD-05PUB).
MPC5200 USB requires additional
defines:
CONFIG_USB_CLOCK
for 528 MHz Clock:
0x0001bbbb
CONFIG_USB_CONFIG
for differential
drivers: 0x00001000
for
single ended drivers: 0x00005000
- MMC Support:
The MMC controller on the Intel PXA
is supported. To
enable
this define CONFIG_MMC. The MMC can be
accessed
from the boot prompt by mapping the device
to physical memory similar to flash. Command line
is
enabled with
CFG_CMD_MMC. The MMC driver also works with
the FAT fs. This is enabled with CFG_CMD_FAT.
-
Journaling Flash filesystem support:
CONFIG_JFFS2_NAND,
CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
CONFIG_JFFS2_NAND_DEV
Define these for a default partition on a NAND
device
CFG_JFFS2_FIRST_SECTOR,
CFG_JFFS2_FIRST_BANK,
CFG_JFFS2_NUM_BANKS
Define
these for a default partition on a NOR device
CFG_JFFS_CUSTOM_PART
Define this to create an own
partition. You have to provide a
function
struct part_info* jffs2_part_info(int part_num)
If you define only one JFFS2
partition you may also want to
#define
CFG_JFFS_SINGLE_PART 1
to disable the command chpart. This
is the default when you
have
not defined a custom partition
- Keyboard Support:
CONFIG_ISA_KEYBOARD
Define this to enable standard
(PC-Style) keyboard
support
CONFIG_I8042_KBD
Standard PC keyboard driver with US
(is default) and
GERMAN
key layout (switch via environment 'keymap=de') support.
Export function i8042_kbd_init,
i8042_tstc and i8042_getc
for
cfb_console. Supports cursor blinking.
- Video support:
CONFIG_VIDEO
Define this to enable video support
(for output to
video).
CONFIG_VIDEO_CT69000
Enable Chips & Technologies
69000 Video chip
CONFIG_VIDEO_SMI_LYNXEM
Enable Silicon Motion SMI
712/710/810 Video chip. The
video
output is selected via environment 'videoout'
(1 = LCD and 2 = CRT). If videoout is undefined, CRT
is
assumed.
For the CT69000 and SMI_LYNXEM
drivers, videomode is
selected
via environment 'videomode'. Two diferent ways
are possible:
-
"videomode=num" 'num' is a
standard LiLo mode numbers.
Following
standard modes are supported (* is
default):
Colors 640x480
800x600 1024x768 1152x864 1280x1024
-------------+---------------------------------------------
8 bits | 0x301* 0x303
0x305 0x161 0x307
15 bits | 0x310 0x313 0x316 0x162 0x319
16 bits | 0x311 0x314 0x317 0x163 0x31A
24 bits | 0x312 0x315 0x318 ? 0x31B
-------------+---------------------------------------------
(i.e. setenv videomode 317; saveenv;
reset;)
-
"videomode=bootargs" all the video parameters are parsed
from the bootargs. (See
drivers/videomodes.c)
CONFIG_VIDEO_SED13806
Enable Epson SED13806 driver. This
driver supports 8bpp
and
16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
or CONFIG_VIDEO_SED13806_16BPP
- Keyboard
Support:
CONFIG_KEYBOARD
Define this to enable a custom
keyboard support.
This
simply calls drv_keyboard_init() which must be
defined in your board-specific files.
The only board using this so far is
RBC823.
- LCD Support: CONFIG_LCD
Define this to enable LCD support
(for output to LCD
display);
also select one of the supported displays
by
defining one of these:
CONFIG_NEC_NL6448AC33:
NEC NL6448AC33-18. Active,
color, single scan.
CONFIG_NEC_NL6448BC20
NEC NL6448BC20-08. 6.5",
640x480.
Active,
color, single scan.
CONFIG_NEC_NL6448BC33_54
NEC NL6448BC33-54. 10.4",
640x480.
Active,
color, single scan.
CONFIG_SHARP_16x9
Sharp
320x240. Active, color, single scan.
It
isn't 16x9, and I am not sure what it is.
CONFIG_SHARP_LQ64D341
Sharp LQ64D341 display, 640x480.
Active, color, single
scan.
CONFIG_HLD1045
HLD1045 display,
640x480.
Active,
color, single scan.
CONFIG_OPTREX_BW
Optrex CBL50840-2 NF-FW 99 22 M5
or
Hitachi LMG6912RPFC-00T
or
Hitachi SP14Q002
320x240.
Black & white.
Normally
display is black on white background; define
CFG_WHITE_ON_BLACK to get it inverted.
-
Splash Screen Support: CONFIG_SPLASH_SCREEN
If this option is set, the environment is checked
for
a variable
"splashimage". If found, the usual display
of logo, copyright and system
information on the LCD
is
suppressed and the BMP image at the address
specified in "splashimage" is loaded instead.
The
console is redirected
to the "nulldev", too. This
allows
for a "silent" boot where a splash screen is
loaded very quickly after
power-on.
- Compression support:
CONFIG_BZIP2
If
this option is set, support for bzip2 compressed
images is included. If not, only uncompressed and
gzip
compressed images
are supported.
NOTE:
the bzip2 algorithm requires a lot of RAM, so
the malloc area (as defined by CFG_MALLOC_LEN)
should
be at least
4MB.
- MII/PHY support:
CONFIG_PHY_ADDR
The address of PHY on MII bus.
CONFIG_PHY_CLOCK_FREQ (ppc4xx)
The clock frequency of the MII
bus
CONFIG_PHY_GIGE
If this option is set, support for
speed/duplex
detection of
Gigabit PHY is included.
CONFIG_PHY_RESET_DELAY
Some PHY like Intel LXT971A need
extra delay after
reset
before any MII register access is possible.
For such PHY, set this option to the usec delay
required. (minimum 300usec for
LXT971A)
CONFIG_PHY_CMD_DELAY
(ppc4xx)
Some PHY
like Intel LXT971A need extra delay after
command
issued before MII status register can be read
- Ethernet
address:
CONFIG_ETHADDR
CONFIG_ETH2ADDR
CONFIG_ETH3ADDR
Define a default value for ethernet
address to use
for the
respective ethernet interface, in case this
is not determined automatically.
- IP
address:
CONFIG_IPADDR
Define a default value for the IP
address to use for
the
default ethernet interface, in case this is not
determined through e.g. bootp.
- Server IP
address:
CONFIG_SERVERIP
Defines a default value for theIP
address of a TFTP
server
to contact when using the "tftboot" command.
- BOOTP
Recovery Mode:
CONFIG_BOOTP_RANDOM_DELAY
If you have many targets in a
network that try to
boot
using BOOTP, you may want to avoid that all
systems send out BOOTP requests at precisely the
same
moment (which would
happen for instance at recovery
from
a power failure, when all systems will try to
boot, thus flooding the BOOTP server. Defining
CONFIG_BOOTP_RANDOM_DELAY
causes a random delay to be
inserted
before sending out BOOTP requests. The
following
delays are insterted then:
1st
BOOTP request: delay 0 ... 1
sec
2nd BOOTP request: delay 0 ... 2 sec
3rd BOOTP request: delay 0 ... 4 sec
4th and following
BOOTP requests: delay 0 ... 8 sec
- DHCP
Advanced Options:
CONFIG_BOOTP_MASK
You can fine tune the DHCP
functionality by adding
these
flags to the CONFIG_BOOTP_MASK define:
CONFIG_BOOTP_DNS2 - If a DHCP client requests the
DNS
serverip from a DHCP
server, it is possible that more
than
one DNS serverip is offered to the client.
If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
serverip will be stored in the
additional environment
variable
"dnsip2". The first DNS serverip is always
stored in the variable
"dnsip", when CONFIG_BOOTP_DNS
is
added to the CONFIG_BOOTP_MASK.
CONFIG_BOOTP_SEND_HOSTNAME
- Some DHCP servers are capable
to
do a dynamic update of a DNS server. To do this, they
need the hostname of the DHCP
requester.
If
CONFIG_BOOP_SEND_HOSTNAME is added to the
CONFIG_BOOTP_MASK,
the content of the "hostname"
environment
variable is passed as option 12 to
the
DHCP server.
- CDP
Options:
CONFIG_CDP_DEVICE_ID
The device id used in CDP trigger
frames.
CONFIG_CDP_DEVICE_ID_PREFIX
A two character string which is
prefixed to the MAC address
of
the device.
CONFIG_CDP_PORT_ID
A printf format string which
contains the ascii name of
the
port. Normally is set to "eth%d" which sets
eth0 for the first ethernet, eth1
for the second etc.
CONFIG_CDP_CAPABILITIES
A 32bit integer which indicates the
device capabilities;
0x00000010
for a normal host which does not forwards.
CONFIG_CDP_VERSION
An ascii string containing the version of the
software.
CONFIG_CDP_PLATFORM
An ascii string containing the name
of the platform.
CONFIG_CDP_TRIGGER
A 32bit integer sent on the
trigger.
CONFIG_CDP_POWER_CONSUMPTION
A 16bit integer containing the power
consumption of the
device
in .1 of milliwatts.
CONFIG_CDP_APPLIANCE_VLAN_TYPE
A byte containing the id of the
VLAN.
- Status LED: CONFIG_STATUS_LED
Several configurations allow to
display the current
status
using a LED. For instance, the LED will blink
fast while running U-Boot code, stop blinking as
soon as a reply to a BOOTP request
was received, and
start
blinking slow once the Linux kernel is running
(supported by a status LED driver in the Linux
kernel). Defining CONFIG_STATUS_LED
enables this
feature in
U-Boot.
- CAN Support: CONFIG_CAN_DRIVER
Defining CONFIG_CAN_DRIVER enables
CAN driver support
on
those systems that support this (optional)
feature, like the TQM8xxL modules.
- I2C
Support: CONFIG_HARD_I2C |
CONFIG_SOFT_I2C
These
enable I2C serial bus commands. Defining either of
(but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C
will
include the
appropriate I2C driver for the selected cpu.
This will allow you to use i2c commands at the
u-boot
command line (as
long as you set CFG_CMD_I2C in
CONFIG_COMMANDS)
and communicate with i2c based realtime
clock
chips. See common/cmd_i2c.c for a description of the
command line interface.
CONFIG_HARD_I2C selects the CPM
hardware driver for I2C.
CONFIG_SOFT_I2C
configures u-boot to use a software (aka
bit-banging)
driver instead of CPM or similar hardware
support
for I2C.
There are
several other quantities that must also be
defined when you define CONFIG_HARD_I2C or
CONFIG_SOFT_I2C.
In
both cases you will need to define CFG_I2C_SPEED
to be the frequency (in Hz) at which you wish your i2c
bus
to run and
CFG_I2C_SLAVE to be the address of this node (ie
the cpu's i2c node address).
Now, the u-boot i2c code for the
mpc8xx (cpu/mpc8xx/i2c.c)
sets
the cpu up as a master node and so its address should
therefore be cleared to 0 (See, eg,
MPC823e User's Manual
p.16-473).
So, set CFG_I2C_SLAVE to 0.
That's
all that's required for CONFIG_HARD_I2C.
If you use the software i2c interface (CONFIG_SOFT_I2C)
then the following macros need to be
defined (examples are
from
include/configs/lwmon.h):
I2C_INIT
(Optional). Any commands necessary
to enable the I2C
controller
or configure ports.
eg:
#define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
I2C_PORT
(Only for MPC8260 CPU). The I/O port
to use (the code
assumes
both bits are on the same port). Valid values
are 0..3 for ports A..D.
I2C_ACTIVE
The code necessary to make the I2C
data line active
(driven). If the data line is open collector,
this
define can be
null.
eg: #define
I2C_ACTIVE (immr->im_cpm.cp_pbdir |=
PB_SDA)
I2C_TRISTATE
The code necessary to make the I2C
data line tri-stated
(inactive). If the data line is open collector,
this
define can be
null.
eg: #define
I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
I2C_READ
Code that returns TRUE if the I2C
data line is high,
FALSE
if it is low.
eg:
#define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
I2C_SDA(bit)
If <bit> is TRUE, sets the I2C
data line high. If it
is
FALSE, it clears it (low).
eg:
#define I2C_SDA(bit) \
if(bit)
immr->im_cpm.cp_pbdat |= PB_SDA;
\
else immr->im_cpm.cp_pbdat &= ~PB_SDA
I2C_SCL(bit)
If <bit> is TRUE, sets the I2C
clock line high. If it
is FALSE, it clears it (low).
eg: #define I2C_SCL(bit) \
if(bit)
immr->im_cpm.cp_pbdat |= PB_SCL;
\
else immr->im_cpm.cp_pbdat &= ~PB_SCL
I2C_DELAY
This delay is invoked four times per
clock cycle so this
controls
the rate of data transfer. The data
rate thus
is 1 /
(I2C_DELAY * 4). Often defined to be something
like:
#define
I2C_DELAY udelay(2)
CFG_I2C_INIT_BOARD
When a board is reset during an i2c
bus transfer
chips might
think that the current transfer is still
in
progress. On some boards it is possible to access
the i2c SCLK line directly, either by using the
processor pin as a GPIO or by having
a second pin
connected to
the bus. If this option is defined a
custom
i2c_init_board() routine in boards/xxx/board.c
is run early in the boot sequence.
CONFIG_I2CFAST (PPC405GP|PPC405EP
only)
This option
enables configuration of bi_iic_fast[] flags
in u-boot bd_info structure based on u-boot
environment
variable
"i2cfast". (see also i2cfast)
- SPI Support: CONFIG_SPI
Enables SPI driver (so far only
tested with
SPI EEPROM,
also an instance works with Crystal A/D and
D/As on the SACSng board)
CONFIG_SPI_X
Enables extended (16-bit) SPI EEPROM
addressing.
(symmetrical
to CONFIG_I2C_X)
CONFIG_SOFT_SPI
Enables a software (bit-bang) SPI
driver rather than
using
hardware support. This is a general purpose
driver that only requires three general I/O port
pins
(two outputs, one
input) to function. If this is
defined,
the board configuration must define several
SPI configuration items (port pins to use, etc).
For
an example, see
include/configs/sacsng.h.
- FPGA Support: CONFIG_FPGA_COUNT
Specify the number of FPGA devices
to support.
CONFIG_FPGA
Used to specify the types of FPGA
devices. For example,
#define CONFIG_FPGA CFG_XILINX_VIRTEX2
CFG_FPGA_PROG_FEEDBACK
Enable printing of hash marks during
FPGA configuration.
CFG_FPGA_CHECK_BUSY
Enable checks on FPGA configuration
interface busy
status by
the configuration function. This option
will
require a board or device specific function to
be written.
CONFIG_FPGA_DELAY
If defined, a function that provides
delays in the FPGA
configuration
driver.
CFG_FPGA_CHECK_CTRLC
Allow Control-C to interrupt FPGA
configuration
CFG_FPGA_CHECK_ERROR
Check for configuration errors
during FPGA bitfile
loading.
For example, abort during Virtex II
configuration
if the INIT_B line goes low (which
indicated
a CRC error).
CFG_FPGA_WAIT_INIT
Maximum time to wait for the INIT_B
line to deassert
after
PROB_B has been deasserted during a Virtex II
FPGA configuration sequence. The default time is
500
mS.
CFG_FPGA_WAIT_BUSY
Maximum time to wait for BUSY to
deassert during
Virtex II
FPGA configuration. The default is 5 mS.
CFG_FPGA_WAIT_CONFIG
Time to wait after FPGA configuration. The default
is
200 mS.
-
Configuration Management:
CONFIG_IDENT_STRING
If defined, this string will be
added to the U-Boot
version
information (U_BOOT_VERSION)
- Vendor Parameter Protection:
U-Boot considers the values of the
environment
variables
"serial#" (Board Serial Number) and
"ethaddr" (Ethernet Address) to be parameters
that
are set once by the
board vendor / manufacturer, and
protects
these variables from casual modification by
the user. Once set, these variables are read-only,
and write or delete attempts are
rejected. You can
change
this behviour:
If
CONFIG_ENV_OVERWRITE is #defined in your config
file, the write protection for vendor parameters is
completely disabled. Anybody can
change or delete
these
parameters.
Alternatively,
if you #define _both_ CONFIG_ETHADDR
_and_
CONFIG_OVERWRITE_ETHADDR_ONCE, a default
ethernet
address is installed in the environment,
which
can be changed exactly ONCE by the user. [The
serial# is unaffected by this, i. e. it remains
read-only.]
- Protected
RAM:
CONFIG_PRAM
Define this variable to enable the
reservation of
"protected
RAM", i. e. RAM which is not overwritten
by U-Boot. Define CONFIG_PRAM to hold the number of
kB you want to reserve for pRAM. You
can overwrite
this
default value by defining an environment
variable
"pram" to the number of kB you want to
reserve. Note that the board info structure will
still show the full amount of RAM.
If pRAM is
reserved, a
new environment variable "mem" will
automatically be defined to hold the amount of
remaining RAM in a form that can be
passed as boot
argument
to Linux, for instance like that:
setenv
bootargs ... mem=\$(mem)
saveenv
This way you can tell Linux not to
use this memory,
either,
which results in a memory region that will
not be affected by reboots.
*WARNING* If your board
configuration uses automatic
detection
of the RAM size, you must make sure that
this
memory test is non-destructive. So far, the
following board configurations are known to be
"pRAM-clean":
ETX094, IVMS8, IVML24, SPD8xx,
TQM8xxL,
HERMES,
IP860, RPXlite, LWMON, LANTEC,
PCU_E,
FLAGADM, TQM8260
- Error Recovery:
CONFIG_PANIC_HANG
Define this variable to stop the system in case of
a
fatal error, so that
you have to reset it manually.
This
is probably NOT a good idea for an embedded
system where you want to system to reboot
automatically as fast as possible,
but it may be
useful
during development since you can try to debug
the conditions that lead to the situation.
CONFIG_NET_RETRY_COUNT
This variable defines the number of
retries for
network
operations like ARP, RARP, TFTP, or BOOTP
before
giving up the operation. If not defined, a
default value of 5 is used.
- Command
Interpreter:
CFG_AUTO_COMPLETE
Enable auto completion of commands
using TAB.
CFG_HUSH_PARSER
Define this variable to enable the
"hush" shell (from
Busybox)
as command line interpreter, thus enabling
powerful command line syntax like
if...then...else...fi conditionals
or `&&' and '||'
constructs
("shell scripts").
If
undefined, you get the old, much simpler behaviour
with a somewhat smaller memory footprint.
CFG_PROMPT_HUSH_PS2
This defines the secondary prompt
string, which is
printed
when the command interpreter needs more input
to complete a command. Usually "> ".
Note:
In the current implementation, the local variables
space and global environment
variables space are
separated.
Local variables are those you define by
simply
typing `name=value'. To access a local
variable
later on, you have write `$name' or
`${name}';
to execute the contents of a variable
directly type `$name' at the command
prompt.
Global
environment variables are those you use
setenv/printenv
to work with. To run a command stored
in
such a variable, you need to use the run command,
and you must not use the '$' sign to access them.
To store commands and special
characters in a
variable,
please use double quotation marks
surrounding
the whole text of the variable, instead
of
the backslashes before semicolons and special
symbols.
- Default Environment:
CONFIG_EXTRA_ENV_SETTINGS
Define this to contain any number of
null terminated
strings
(variable = value pairs) that will be part of
the default environment compiled into the boot
image.
For example,
place something like this in your
board's
config file:
#define
CONFIG_EXTRA_ENV_SETTINGS \
"myvar1=value1\0"
\
"myvar2=value2\0"
Warning: This method is based on
knowledge about the
internal
format how the environment is stored by the
U-Boot code. This is NOT an official, exported
interface! Although it is unlikely
that this format
will
change soon, there is no guarantee either.
You better know what you are doing here.
Note: overly (ab)use of the default
environment is
discouraged.
Make sure to check other ways to preset
the
environment like the autoscript function or the
boot command first.
- DataFlash Support:
CONFIG_HAS_DATAFLASH
Defining this option enables
DataFlash features and
allows
to read/write in Dataflash via the standard
commands cp, md...
- SystemACE Support:
CONFIG_SYSTEMACE
Adding this option adds support for
Xilinx SystemACE
chips
attached via some sort of local bus. The address
of the chip must alsh be defined in the
CFG_SYSTEMACE_BASE macro. For
example:
#define
CONFIG_SYSTEMACE
#define
CFG_SYSTEMACE_BASE 0xf0000000
When
SystemACE support is added, the "ace" device type
becomes available to the fat
commands, i.e. fatls.
- Show boot progress:
CONFIG_SHOW_BOOT_PROGRESS
Defining this option allows to add
some board-
specific code
(calling a user-provided function
"show_boot_progress(int)")
that enables you to show
the
system's boot progress on some display (for
example, some LED's) on your board. At the moment,
the following checkpoints are
implemented:
Arg Where When
1 common/cmd_bootm.c before attempting to boot an image
-1 common/cmd_bootm.c Image header has bad magic number
2 common/cmd_bootm.c Image header has correct magic
number
-2 common/cmd_bootm.c Image
header has bad checksum
3 common/cmd_bootm.c Image header has correct checksum
-3 common/cmd_bootm.c Image data has bad checksum
4 common/cmd_bootm.c Image data has correct checksum
-4 common/cmd_bootm.c Image is for unsupported
architecture
5 common/cmd_bootm.c Architecture check OK
-5 common/cmd_bootm.c Wrong Image Type (not kernel, multi,
standalone)
6 common/cmd_bootm.c Image Type check OK
-6 common/cmd_bootm.c gunzip uncompression error
-7 common/cmd_bootm.c Unimplemented compression type
7 common/cmd_bootm.c Uncompression OK
-8 common/cmd_bootm.c Wrong Image Type (not kernel, multi,
standalone)
8 common/cmd_bootm.c Image Type check OK
-9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks,
QNX)
9 common/cmd_bootm.c Start
initial ramdisk verification
-10 common/cmd_bootm.c Ramdisk header has bad magic number
-11 common/cmd_bootm.c Ramdisk header has bad
checksum
10 common/cmd_bootm.c Ramdisk header is OK
-12 common/cmd_bootm.c Ramdisk data has bad checksum
11 common/cmd_bootm.c Ramdisk data has correct checksum
12 common/cmd_bootm.c Ramdisk verification complete, start
loading
-13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
13 common/cmd_bootm.c Start multifile image verification
14 common/cmd_bootm.c No initial ramdisk, no multifile,
continue.
15 common/cmd_bootm.c All preparation done, transferring control to OS
-30 lib_ppc/board.c Fatal error, hang the system
-31 post/post.c POST test failed, detected by
post_output_backlog()
-32 post/post.c POST
test failed, detected by post_run_single()
-1 common/cmd_doc.c Bad usage of "doc" command
-1 common/cmd_doc.c No boot device
-1 common/cmd_doc.c Unknown Chip ID on boot device
-1 common/cmd_doc.c Read Error on boot device
-1 common/cmd_doc.c Image header has bad magic number
-1 common/cmd_ide.c Bad usage of "ide" command
-1 common/cmd_ide.c No boot device
-1 common/cmd_ide.c Unknown boot device
-1 common/cmd_ide.c Unknown partition table
-1 common/cmd_ide.c Invalid partition type
-1 common/cmd_ide.c Read Error on boot device
-1 common/cmd_ide.c Image header has bad magic number
-1 common/cmd_nand.c Bad usage of "nand" command
-1 common/cmd_nand.c No boot device
-1 common/cmd_nand.c Unknown Chip ID on boot device
-1 common/cmd_nand.c Read Error on boot device
-1 common/cmd_nand.c Image header has bad magic number
-1 common/env_common.c Environment has a bad CRC, using
default
Modem Support:
--------------
[so far
only for SMDK2400 and TRAB boards]
- Modem support endable:
CONFIG_MODEM_SUPPORT
-
RTS/CTS Flow control enable:
CONFIG_HWFLOW
-
Modem debug support:
CONFIG_MODEM_SUPPORT_DEBUG
Enables debugging stuff (char
screen[1024], dbg())
for
modem support. Useful only with BDI2000.
- Interrupt support
(PPC):
There are
common interrupt_init() and timer_interrupt()
for all PPC archs. interrupt_init() calls
interrupt_init_cpu()
for
cpu specific initialization. interrupt_init_cpu()
should set decrementer_count to appropriate value.
If
cpu resets decrementer
automatically after interrupt
(ppc4xx)
it should set decrementer_count to zero.
timer_interrupt()
calls timer_interrupt_cpu() for cpu
specific
handling. If board has watchdog / status_led
/ other_activity_monitor it works automatically
from
general
timer_interrupt().
- General:
In the target system modem support is enabled when
a
specific key (key
combination) is pressed during
power-on.
Otherwise U-Boot will boot normally
(autoboot).
The key_pressed() fuction is called from
board_init().
Currently key_pressed() is a dummy
function,
returning 1 and thus enabling modem
initialization.
If there are no modem init strings
in the
environment,
U-Boot proceed to autoboot; the
previous
output (banner, info printfs) will be
supressed,
though.
See also:
doc/README.Modem
Configuration Settings:
-----------------------
-
CFG_LONGHELP: Defined when you want long help messages included;
undefine this when you're short of
memory.
- CFG_PROMPT: This
is what U-Boot prints on the console to
prompt
for user input.
- CFG_CBSIZE: Buffer
size for input from the Console
- CFG_PBSIZE: Buffer size for Console output
- CFG_MAXARGS: max. Number of arguments accepted for
monitor commands
- CFG_BARGSIZE: Buffer size for Boot Arguments
which are passed to
the
application (usually a Linux kernel) when it is
booted
- CFG_BAUDRATE_TABLE:
List of legal baudrate settings for
this board.
- CFG_CONSOLE_INFO_QUIET
Suppress display of console information at boot.
-
CFG_CONSOLE_IS_IN_ENV
If
the board specific function
extern
int overwrite_console (void);
returns
1, the stdin, stderr and stdout are switched to the
serial port, else the settings in
the environment are used.
- CFG_CONSOLE_OVERWRITE_ROUTINE
Enable the call to
overwrite_console().
- CFG_CONSOLE_ENV_OVERWRITE
Enable overwrite of previous console
environment settings.
- CFG_MEMTEST_START, CFG_MEMTEST_END:
Begin and End addresses of the area
used by the
simple memory
test.
- CFG_ALT_MEMTEST:
Enable
an alternate, more extensive memory test.
-
CFG_MEMTEST_SCRATCH:
Scratch
address used by the alternate memory test
You
only need to set this if address zero isn't writeable
-
CFG_TFTP_LOADADDR:
Default
load address for network file downloads
-
CFG_LOADS_BAUD_CHANGE:
Enable
temporary baudrate change while serial download
-
CFG_SDRAM_BASE:
Physical
start address of SDRAM. _Must_ be 0 here.
- CFG_MBIO_BASE:
Physical start address of
Motherboard I/O (if using a
Cogent
motherboard)
- CFG_FLASH_BASE:
Physical
start address of Flash memory.
- CFG_MONITOR_BASE:
Physical start address of boot
monitor code (set by
make
config files to be same as the text base address
(TEXT_BASE) used when linking) - same as
CFG_FLASH_BASE when booting from
flash.
- CFG_MONITOR_LEN:
Size
of memory reserved for monitor code, used to
determine _at_compile_time_ (!) if the environment
is
embedded within the
U-Boot image, or in a separate
flash
sector.
- CFG_MALLOC_LEN:
Size
of DRAM reserved for malloc() use.
- CFG_BOOTMAPSZ:
Maximum size of memory mapped by the
startup code of
the Linux
kernel; all data that must be processed by
the Linux kernel (bd_info, boot arguments,
eventually
initrd image)
must be put below this limit.
- CFG_MAX_FLASH_BANKS:
Max number of Flash memory
banks
- CFG_MAX_FLASH_SECT:
Max
number of sectors on a Flash chip
- CFG_FLASH_ERASE_TOUT:
Timeout for Flash erase operations
(in ms)
- CFG_FLASH_WRITE_TOUT:
Timeout for Flash write operations (in ms)
-
CFG_FLASH_LOCK_TOUT
Timeout
for Flash set sector lock bit operation (in ms)
-
CFG_FLASH_UNLOCK_TOUT
Timeout
for Flash clear lock bits operation (in ms)
-
CFG_FLASH_PROTECTION
If
defined, hardware flash sectors protection is used
instead of U-Boot software protection.
-
CFG_DIRECT_FLASH_TFTP:
Enable
TFTP transfers directly to flash memory;
without
this option such a download has to be
performed
in two steps: (1) download to RAM, and (2)
copy from RAM to flash.
The two-step approach is usually
more reliable, since
you
can check if the download worked before you erase
the flash, but in some situations (when sytem RAM
is
too limited to allow
for a tempory copy of the
downloaded
image) this option may be very useful.
- CFG_FLASH_CFI:
Define if the flash driver uses
extra elements in the
common
flash structure for storing flash geometry.
-
CFG_FLASH_CFI_DRIVER
This
option also enables the building of the cfi_flash driver
in the drivers directory
-
CFG_RX_ETH_BUFFER:
Defines
the number of ethernet receive buffers. On some
ethernet controllers it is recommended to set this
value
to 8 or even higher
(EEPRO100 or 405 EMAC), since all
buffers
can be full shortly after enabling the interface
on high ethernet traffic.
Defaults to 4 if not defined.
The following
definitions that deal with the placement and management
of environment
data (variable area); in general, we support the
following
configurations:
- CFG_ENV_IS_IN_FLASH:
Define this if the environment is in flash
memory.
a) The
environment occupies one whole flash sector, which is
"embedded" in the text segment with the U-Boot code.
This
happens usually with "bottom boot sector" or "top
boot
sector" type flash chips, which have several smaller
sectors at the start or the end. For instance, such a
layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
such a case you would place the environment in one of the
4 kB sectors - with U-Boot code before and after it. With
"top boot sector" type flash chips, you would put the
environment in one of the last sectors, leaving a gap
between U-Boot and the environment.
- CFG_ENV_OFFSET:
Offset of environment data (variable area)
to the
beginning of flash memory; for instance,
with bottom boot
type flash chips the second sector can be
used: the offset
for this sector is given here.
CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
- CFG_ENV_ADDR:
This is just another way to specify the start address of
the flash sector containing the environment (instead of
CFG_ENV_OFFSET).
-
CFG_ENV_SECT_SIZE:
Size of the sector containing the
environment.
b)
Sometimes flash chips have few, equal sized, BIG sectors.
In such a case you don't want to spend a whole sector for
the environment.
-
CFG_ENV_SIZE:
If you use this in combination with
CFG_ENV_IS_IN_FLASH
and CFG_ENV_SECT_SIZE, you can specify to
use only a part
of this flash sector for the environment.
This saves
memory for the RAM copy of the
environment.
It may also save flash memory if you decide
to use this
when your environment is
"embedded" within U-Boot code,
since then the remainder of the flash
sector could be used
for U-Boot code. It should be pointed out
that this is
STRONGLY DISCOURAGED from a robustness
point of view:
updating the environment in flash makes it
always
necessary to erase the WHOLE sector. If
something goes
wrong before the contents has been restored
from a copy in
RAM, your target system will be dead.
- CFG_ENV_ADDR_REDUND
CFG_ENV_SIZE_REDUND
These settings describe a second storage
area used to hold
a redundand copy of the environment data,
so that there is
a valid backup copy in case there is a
power failure during
a "saveenv" operation.
BE
CAREFUL! Any changes to the flash layout, and some changes to the
source
code will make it necessary to adapt <board>/u-boot.lds*
accordingly!
-
CFG_ENV_IS_IN_NVRAM:
Define
this if you have some non-volatile memory device
(NVRAM, battery buffered SRAM) which you want to use for
the
environment.
- CFG_ENV_ADDR:
- CFG_ENV_SIZE:
These two #defines are used to determin the memory area you
want to use for environment. It is assumed that this memory
can just be read and written to, without any special
provision.
BE CAREFUL! The first access to the environment
happens quite early
in U-Boot initalization (when we try to get the
setting of for the
console baudrate). You *MUST* have mappend your NVRAM
area then, or
U-Boot will hang.
Please note that even with
NVRAM we still use a copy of the
environment in RAM: we could work on
NVRAM directly, but we want to
keep settings there always unmodified
except somebody uses "saveenv"
to save the current
settings.
- CFG_ENV_IS_IN_EEPROM:
Use this if you have an EEPROM or similar
serial access
device and a
driver for it.
-
CFG_ENV_OFFSET:
-
CFG_ENV_SIZE:
These two #defines specify the offset and
size of the
environment area within the total memory of
your EEPROM.
-
CFG_I2C_EEPROM_ADDR:
If defined, specified the chip address of
the EEPROM device.
The default address is zero.
- CFG_EEPROM_PAGE_WRITE_BITS:
If defined, the number of bits used to address bytes in a
single page in the EEPROM device.
A 64 byte page, for example
would require six bits.
- CFG_EEPROM_PAGE_WRITE_DELAY_MS:
If defined, the number of milliseconds to delay between
page writes. The default is zero
milliseconds.
-
CFG_I2C_EEPROM_ADDR_LEN:
The length in bytes of the EEPROM memory
array address. Note
that this is NOT the chip address length!
- CFG_I2C_EEPROM_ADDR_OVERFLOW:
EEPROM chips that implement "address overflow" are ones
like Catalyst 24WC04/08/16 which has 9/10/11 bits of
address and the extra bits end up in the "chip address"
bit
slots. This makes a 24WC08 (1Kbyte) chip look like four 256
byte chips.
Note that we consider the length of the
address field to
still be one byte because the extra address
bits are hidden
in the chip address.
- CFG_EEPROM_SIZE:
The size in bytes of the EEPROM device.
-
CFG_ENV_IS_IN_DATAFLASH:
Define
this if you have a DataFlash memory device which you
want to use for the environment.
- CFG_ENV_OFFSET:
- CFG_ENV_ADDR:
- CFG_ENV_SIZE:
These three #defines specify the offset and size of the
environment area within the total memory of your DataFlash placed
at the specified address.
- CFG_ENV_IS_IN_NAND:
Define this if you have a NAND device
which you want to use
for the
environment.
-
CFG_ENV_OFFSET:
-
CFG_ENV_SIZE:
These two #defines specify the offset and
size of the environment
area within the first NAND device.
-
CFG_SPI_INIT_OFFSET
Defines
offset to the initial SPI buffer area in DPRAM. The
area is used at an early stage (ROM part)
if the environment
is
configured to reside in the SPI EEPROM: We need a 520 byte
scratch DPRAM area. It is used between the
two initialization
calls
(spi_init_f() and spi_init_r()). A value of 0xB00 seems
to be a good choice since it makes it far
enough from the
start of the
data area as well as from the stack pointer.
Please note that the
environment is read-only as long as the monitor
has been relocated to RAM
and a RAM copy of the environment has been
created; also, when using
EEPROM you will have to use getenv_r()
until then to read environment
variables.
The environment is protected by a CRC32 checksum. Before
the monitor
is relocated into RAM, as a result of a bad CRC you will be
working
with the compiled-in default environment - *silently*!!! [This
is
necessary, because the first environment variable we need is the
"baudrate"
setting for the console - if we have a bad CRC, we don't
have any device
yet where we could complain.]
Note: once the monitor has been
relocated, then it will complain if
the default environment is used; a new
CRC is computed as soon as you
use the "saveenv" command to
store a valid environment.
- CFG_FAULT_ECHO_LINK_DOWN:
Echo the inverted Ethernet link
state to the fault LED.
Note:
If this option is active, then CFG_FAULT_MII_ADDR
also needs
to be defined.
- CFG_FAULT_MII_ADDR:
MII address of the PHY to check for the Ethernet link
state.
- CFG_64BIT_VSPRINTF:
Makes
vsprintf (and all *printf functions) support printing
of 64bit values by using the L
quantifier
- CFG_64BIT_STRTOUL:
Adds simple_strtoull that returns a 64bit value
Low
Level (hardware related) configuration options:
---------------------------------------------------
-
CFG_CACHELINE_SIZE:
Cache
Line Size of the CPU.
- CFG_DEFAULT_IMMR:
Default address of the IMMR after
system reset.
Needed
on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
and RPXsuper) to be able to adjust the position of
the IMMR register after a
reset.
- Floppy Disk Support:
CFG_FDC_DRIVE_NUMBER
the default drive number (default
value 0)
CFG_ISA_IO_STRIDE
defines the spacing between fdc
chipset registers
(default
value 1)
CFG_ISA_IO_OFFSET
defines the offset of register from
address. It
depends on
which part of the data bus is connected to
the fdc chipset. (default value 0)
If CFG_ISA_IO_STRIDE
CFG_ISA_IO_OFFSET and
CFG_FDC_DRIVE_NUMBER
are undefined, they take their
default
value.
if
CFG_FDC_HW_INIT is defined, then the function
fdc_hw_init() is called at the beginning of the FDC
setup. fdc_hw_init() must be
provided by the board
source
code. It is used to make hardware dependant
initializations.
- CFG_IMMR: Physical address of the Internal Memory.
DO NOT CHANGE unless you know
exactly what you're
doing!
(11-4) [MPC8xx/82xx systems only]
- CFG_INIT_RAM_ADDR:
Start address of memory area that
can be used for
initial
data and stack; please note that this must be
writable memory that is working WITHOUT special
initialization, i. e. you CANNOT use
normal RAM which
will
become available only after programming the
memory controller and running certain
initialization
sequences.
U-Boot uses the following memory
types:
- MPC8xx and
MPC8260: IMMR (internal memory of the CPU)
- MPC824X: data cache
- PPC4xx: data
cache
- CFG_GBL_DATA_OFFSET:
Offset of the initial data structure in the memory
area defined by CFG_INIT_RAM_ADDR.
Usually
CFG_GBL_DATA_OFFSET
is chosen such that the initial
data
is located at the end of the available space
(sometimes written as (CFG_INIT_RAM_END -
CFG_INIT_DATA_SIZE), and the initial
stack is just
below that
area (growing from (CFG_INIT_RAM_ADDR +
CFG_GBL_DATA_OFFSET)
downward.
Note:
On the MPC824X (or other systems
that use the data
cache
for initial memory) the address chosen for
CFG_INIT_RAM_ADDR is basically arbitrary - it must
point to an otherwise UNUSED address
space between
the top of
RAM and the start of the PCI space.
- CFG_SIUMCR: SIU Module Configuration (11-6)
-
CFG_SYPCR: System Protection Control
(11-9)
- CFG_TBSCR: Time
Base Status and Control (11-26)
- CFG_PISCR: Periodic Interrupt Status and Control (11-31)
-
CFG_PLPRCR: PLL, Low-Power, and Reset
Control Register (15-30)
- CFG_SCCR: System
Clock and reset Control Register (15-27)
-
CFG_OR_TIMING_SDRAM:
SDRAM
timing
- CFG_MAMR_PTA:
periodic
timer for refresh
- CFG_DER: Debug
Event Register (37-47)
- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM,
CFG_REMAP_OR_AM,
CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
CFG_OR0_PRELIM, CFG_BR0_PRELIM,
CFG_OR1_REMAP, CFG_OR1_PRELIM,
CFG_BR1_PRELIM:
Memory
Controller Definitions: BR0/1 and OR0/1 (FLASH)
-
SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM,
CFG_BR2_PRELIM,
CFG_OR3_PRELIM,
CFG_BR3_PRELIM:
Memory
Controller Definitions: BR2/3 and OR2/3 (SDRAM)
- CFG_MAMR_PTA,
CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
CFG_MPTPR_1BK_8K, CFG_MAMR_8COL,
CFG_MAMR_9COL:
Machine
Mode Register and Memory Periodic Timer
Prescaler
definitions (SDRAM timing)
- CFG_I2C_UCODE_PATCH,
CFG_I2C_DPMEM_OFFSET [0x1FC0]:
enable
I2C microcode relocation patch (MPC8xx);
define
relocation offset in DPRAM [DSP2]
- CFG_SPI_UCODE_PATCH,
CFG_SPI_DPMEM_OFFSET [0x1FC0]:
enable
SPI microcode relocation patch (MPC8xx);
define
relocation offset in DPRAM [SCC4]
- CFG_USE_OSCCLK:
Use OSCM clock mode on MBX8xx board.
Be careful,
wrong setting
might damage your board. Read
doc/README.MBX
before setting this variable!
- CFG_CPM_POST_WORD_ADDR: (MPC8xx,
MPC8260 only)
Offset of
the bootmode word in DPRAM used by post
(Power
On Self Tests). This definition overrides
#define'd
default value in commproc.h resp.
cpm_8260.h.
-
CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK,
CFG_PCI_MSTR1_LOCAL,
CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE,
CFG_POCMR0_MASK_ATTRIB,
CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS,
CPU_PCI_MEMIO_START,
CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB,
CFG_PCI_MSTR_IO_LOCAL,
CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
Overrides the default PCI memory map
in cpu/mpc8260/pci.c if set.
- CONFIG_ETHER_ON_FEC[12]
Define to enable FEC[12] on a 8xx
series processor.
- CONFIG_FEC[12]_PHY
Define to the hardcoded PHY address which
corresponds
to the given FEC; i. e.
#define CONFIG_FEC1_PHY
4
means that the PHY with
address 4 is connected to FEC1
When
set to -1, means to probe for first available.
-
CONFIG_FEC[12]_PHY_NORXERR
The
PHY does not have a RXERR line (RMII only).
(so program the FEC to ignore it).
-
CONFIG_RMII
Enable RMII
mode for all FECs.
Note
that this is a global option, we can't
have
one FEC in standard MII mode and another in RMII mode.
-
CONFIG_CRC32_VERIFY
Add a
verify option to the crc32 command.
The
syntax is:
=>
crc32 -v <address> <count> <crc32>
Where address/count indicate a
memory area
and crc32 is
the correct crc32 which the
area
should have.
- CONFIG_LOOPW
Add
the "loopw" memory command. This only takes effect if
the memory commands are activated
globally (CFG_CMD_MEM).
- CONFIG_MX_CYCLIC
Add the "mdc" and
"mwc" memory commands. These are cyclic
"md/mw" commands.
Examples:
=>
mdc.b 10 4 500
This
command will print 4 bytes (10,11,12,13) each 500 ms.
=> mwc.l 100 12345678 10
This command will write 12345678 to
address 100 all 10 ms.
This
only takes effect if the memory commands are activated
globally (CFG_CMD_MEM).
Building
the Software:
======================
Building U-Boot has been
tested in native PPC environments (on a
PowerBook G3 running LinuxPPC
2000) and in cross environments
(running RedHat 6.x and 7.x Linux on x86,
Solaris 2.6 on a SPARC, and
NetBSD 1.5 on x86).
If you are not
using a native PPC environment, it is assumed that you
have the GNU cross compiling
tools available in your path and named
with a prefix of
"powerpc-linux-". If this is not the case, (e.g. if
you are
using Monta Vista's Hard Hat Linux CDK 1.2) you must change
the definition
of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
change it to:
CROSS_COMPILE = ppc_4xx-
U-Boot
is intended to be simple to
build. After installing
the
sources you must configure
U-Boot for one specific board type. This
is done by typing:
make NAME_config
where
"NAME_config" is the name of one of the existing
configurations;
the following names are supported:
ADCIOP_config FPS860L_config omap730p2_config
ADS860_config GEN860T_config pcu_e_config
Alaska8220_config
AR405_config GENIETV_config PIP405_config
at91rm9200dk_config GTH_config QS823_config
CANBT_config hermes_config QS850_config
cmi_mpc5xx_config hymod_config QS860T_config
cogent_common_config IP860_config RPXlite_config
cogent_mpc8260_config IVML24_config RPXlite_DW_config
cogent_mpc8xx_config IVMS8_config RPXsuper_config
CPCI405_config JSE_config rsdproto_config
CPCIISER4_config LANTEC_config Sandpoint8240_config
csb272_config lwmon_config sbc8260_config
CU824_config MBX860T_config sbc8560_33_config
DUET_ADS_config MBX_config sbc8560_66_config
EBONY_config MPC8260ADS_config SM850_config
ELPT860_config MPC8540ADS_config SPD823TS_config
ESTEEM192E_config MPC8560ADS_config stxgp3_config
ETX094_config NETVIA_config SXNI855T_config
FADS823_config omap1510inn_config TQM823L_config
FADS850SAR_config omap1610h2_config TQM850L_config
FADS860T_config omap1610inn_config TQM855L_config
FPS850L_config omap5912osk_config TQM860L_config
omap2420h4_config WALNUT405_config
Yukon8220_config
ZPC1900_config
Note:
for some board special configuration names may exist; check if
additional information is available from
the board vendor; for
instance, the TQM823L systems are available without (standard)
or with LCD support. You can select such
additional "features"
when chosing the configuration, i. e.
make TQM823L_config
- will configure for a plain TQM823L, i.
e. no LCD support
make
TQM823L_LCD_config
- will
configure for a TQM823L with U-Boot console on LCD
etc.
Finally, type
"make all", and you should get some working U-Boot
images ready
for download to / installation on your system:
-
"u-boot.bin" is a raw binary image
- "u-boot" is an
image in ELF binary format
- "u-boot.srec" is in Motorola
S-Record format
Please be aware that the Makefiles assume you
are using GNU make, so
for instance on NetBSD you might need to use
"gmake" instead of
native "make".
If
the system board that you have is not listed, then you will need
to port
U-Boot to your hardware platform. To do this, follow these
steps:
1. Add a new configuration option for your
board to the toplevel
"Makefile" and to the "MAKEALL" script, using the
existing
entries as examples.
Note that here and at many other places
boards and other names are listed in alphabetical sort order.
Please
keep this order.
2. Create a new directory to hold your board
specific code. Add any
files
you need. In your board directory, you will need at least
the "Makefile", a
"<board>.c", "flash.c" and
"u-boot.lds".
3. Create
a new configuration file "include/configs/<board>.h" for
your board
3. If you're porting U-Boot to a new CPU, then
also create a new
directory to
hold your CPU specific code. Add any files you need.
4. Run "make <board>_config"
with your new name.
5. Type
"make", and you should get a working "u-boot.srec"
file
to be installed on your
target system.
6. Debug and solve
any problems that might arise.
[Of course, this last step is much harder than it sounds.]
Testing
of U-Boot Modifications, Ports to New Hardware, etc.:
==============================================================
If
you have modified U-Boot sources (for instance added a new board
or support for new
devices, a new CPU, etc.) you
are expected to
provide feedback to the other developers. The feedback
normally takes
the form of a "patch", i. e. a context diff
against a certain (latest
official or latest in CVS) version of U-Boot
sources.
But before you submit such a patch, please verify that your
modifi-
cation did not
break existing code. At least make sure that *ALL* of
the supported boards
compile WITHOUT ANY compiler warnings. To do so,
just run the
"MAKEALL" script, which will configure and build U-Boot
for ALL
supported system. Be warned, this will take a while. You can
select which (cross) compiler
to use by passing a `CROSS_COMPILE'
environment variable to the
script, i. e. to use the cross tools from
MontaVista's Hard Hat Linux you
can type
CROSS_COMPILE=ppc_8xx-
MAKEALL
or to build on a native PowerPC system you can type
CROSS_COMPILE=' ' MAKEALL
See
also "U-Boot Porting Guide" below.
Monitor Commands
- Overview:
============================
go - start application at address 'addr'
run - run commands in an environment
variable
bootm - boot application
image from memory
bootp - boot image
via network using BootP/TFTP protocol
tftpboot- boot image via network
using TFTP protocol
and env variables "ipaddr"
and "serverip"
(and eventually
"gatewayip")
rarpboot- boot image via network using RARP/TFTP
protocol
diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
loads - load S-Record file over serial line
loadb - load binary file over serial line (kermit
mode)
md - memory display
mm - memory modify (auto-incrementing)
nm - memory modify (constant address)
mw - memory write (fill)
cp - memory copy
cmp - memory compare
crc32 - checksum calculation
imd - i2c memory display
imm - i2c memory modify (auto-incrementing)
inm - i2c memory modify (constant address)
imw - i2c memory write (fill)
icrc32 - i2c checksum calculation
iprobe - probe to discover valid I2C chip
addresses
iloop - infinite loop on
address range
isdram - print
SDRAM configuration information
sspi -
SPI utility commands
base - print or
set address offset
printenv- print environment variables
setenv - set environment variables
saveenv -
save environment variables to persistent storage
protect - enable or
disable FLASH write protection
erase -
erase FLASH memory
flinfo -
print FLASH memory information
bdinfo -
print Board Info structure
iminfo -
print header information for application image
coninfo - print console
devices and informations
ide - IDE
sub-system
loop - infinite loop on
address range
loopw - infinite write
loop on address range
mtest - simple
RAM test
icache - enable or
disable instruction cache
dcache -
enable or disable data cache
reset -
Perform RESET of the CPU
echo - echo
args to console
version - print monitor version
help - print online help
? - alias for 'help'
Monitor
Commands - Detailed Description:
========================================
TODO.
For
now: just type "help <command>".
Environment
Variables:
======================
U-Boot supports user
configuration using Environment Variables which
can be made persistent by
saving to Flash memory.
Environment Variables are set using
"setenv", printed using
"printenv", and saved to Flash
using "saveenv". Using "setenv"
without a value can be
used to delete a variable from the
environment. As long as you don't save
the environment you are
working with an in-memory copy. In case the Flash
area containing the
environment is erased by accident, a default
environment is provided.
Some configuration options can be set using
Environment Variables:
baudrate - see
CONFIG_BAUDRATE
bootdelay - see CONFIG_BOOTDELAY
bootcmd -
see CONFIG_BOOTCOMMAND
bootargs - Boot arguments when
booting an RTOS image
bootfile - Name of the image to
load with TFTP
autoload - if set to "no" (any string
beginning with 'n'),
"bootp" will just load perform a
lookup of the
configuration from the BOOTP server, but not
try to
load any image using TFTP
autostart -
if set to "yes", an image loaded using the "bootp",
"rarpboot", "tftpboot" or "diskboot"
commands will
be automatically started (by internally
calling
"bootm")
If set to "no", a standalone image passed to the
"bootm" command will be copied to the load address
(and eventually uncompressed), but NOT be started.
This can be used to load and uncompress arbitrary
data.
i2cfast - (PPC405GP|PPC405EP only)
if set to 'y' configures Linux I2C driver for fast
mode (400kHZ). This environment variable is used in
initialization code. So, for changes to be effective
it must be saved and board must be reset.
initrd_high -
restrict positioning of initrd images:
If this variable is not set, initrd images
will be
copied to the highest possible address in
RAM; this
is usually what you want since it allows
for
maximum initrd size. If for some reason you want
to
make sure that the initrd image is loaded
below the
CFG_BOOTMAPSZ limit, you can set this
environment
variable to a value of "no" or
"off" or "0".
Alternatively, you can set it to a maximum
upper
address to use (U-Boot will still check that
it
does not overwrite the U-Boot stack and
data).
For instance, when you have a system with 16
MB
RAM, and want to reserve 4 MB from use by
Linux,
you can do this by adding
"mem=12M" to the value of
the "bootargs" variable. However,
now you must make
sure that the initrd image is placed in the
first
12 MB as well - this can be done with
setenv initrd_high 00c00000
If you set initrd_high to 0xFFFFFFFF, this
is an
indication to U-Boot that all addresses are
legal
for the Linux kernel, including addresses in
flash
memory. In this case U-Boot will NOT COPY
the
ramdisk at all. This may be useful to reduce
the
boot time on your system, but requires that
this
feature is supported by your Linux
kernel.
ipaddr - IP address; needed for tftpboot
command
loadaddr - Default load address for commands like
"bootp",
"rarpboot", "tftpboot",
"loadb" or "diskboot"
loads_echo - see
CONFIG_LOADS_ECHO
serverip - TFTP server IP address; needed for tftpboot
command
bootretry - see CONFIG_BOOT_RETRY_TIME
bootdelaykey -
see CONFIG_AUTOBOOT_DELAY_STR
bootstopkey - see
CONFIG_AUTOBOOT_STOP_STR
ethprime - When CONFIG_NET_MULTI
is enabled controls which
interface is used first.
ethact -
When CONFIG_NET_MULTI is enabled controls which
interface is
currently active. For example you
can do the following
=> setenv ethact FEC ETHERNET
=> ping 192.168.0.1 # traffic sent on FEC
ETHERNET
=> setenv ethact SCC ETHERNET
=> ping 10.0.0.1 # traffic sent on SCC
ETHERNET
netretry - When set to "no" each network
operation will
either succeed or fail without
retrying.
When set to "once" the network
operation will
fail when all the available network
interfaces
are tried once without success.
Useful on scripts which control the retry operation
themselves.
vlan - When set to a value < 4095 the
traffic over
ethernet is encapsulated/received over
802.1q
VLAN tagged frames.
The following
environment variables may be used and automatically
updated by the network
boot commands ("bootp" and "rarpboot"),
depending the
information provided by your boot server:
bootfile - see above
dnsip -
IP address of your Domain Name Server
dnsip2 - IP address of your
secondary Domain Name Server
gatewayip - IP address of the
Gateway (Router) to use
hostname - Target hostname
ipaddr -
see above
netmask - Subnet Mask
rootpath - Pathname of the
root filesystem on the NFS server
serverip - see above
There
are two special Environment Variables:
serial# - contains
hardware identification information such
as type string and/or serial number
ethaddr -
Ethernet address
These variables can be set only once (usually
during manufacturing of
the board). U-Boot refuses to delete or overwrite
these variables
once they have been set once.
Further
special Environment Variables:
ver - Contains the U-Boot
version string as printed
with the "version" command. This
variable is
readonly (see
CONFIG_VERSION_VARIABLE).
Please note that changes to some
configuration parameters may take
only effect after the next boot (yes,
that's just like Windoze :-).
Command Line Parsing:
=====================
There
are two different command line parsers available with U-Boot:
the old
"simple" one, and the much more powerful "hush"
shell:
Old, simple command line parser:
--------------------------------
-
supports environment variables (through setenv / saveenv commands)
-
several commands on one line, separated by ';'
- variable substitution
using "... $(name) ..." syntax
- special characters ('$', ';')
can be escaped by prefixing with '\',
for example:
setenv
bootcmd bootm \$(address)
- You can also escape text by enclosing in
single apostrophes, for example:
setenv
addip 'setenv bootargs $bootargs
ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
Hush
shell:
-----------
- similar to Bourne shell, with control
structures like
if...then...else...fi, for...do...done; while...do...done,
until...do...done, ...
- supports
environment ("global") variables (through setenv / saveenv
commands) and local shell variables (through
standard shell syntax
"name=value"); only environment variables can be used with
"run"
command
General
rules:
--------------
(1) If a command line (or an environment
variable executed by a "run"
command) contains several commands separated by semicolon, and
one of these commands fails, then the
remaining commands will be
executed anyway.
(2) If you execute several variables with
one call to run (i. e.
calling
run with a list af variables as arguments), any failing
command will cause "run" to
terminate, i. e. the remaining
variables are not executed.
Note for Redundant Ethernet
Interfaces:
=======================================
Some boards
come with redundant ethernet interfaces; U-Boot supports
such
configurations and is capable of automatic selection of a
"working"
interface when needed. MAC assignment works as follows:
Network
interfaces are numbered eth0, eth1, eth2, ... Corresponding
MAC addresses
can be stored in the environment as "ethaddr" (=>eth0),
"eth1addr"
(=>eth1), "eth2addr", ...
If the network interface
stores some valid MAC address (for instance
in SROM), this is used as default
address if there is NO correspon-
ding setting in the environment; if the
corresponding environment
variable is set, this overrides the settings in
the card; that means:
o If the SROM has a valid MAC address, and
there is no address in the
environment, the SROM's address is used.
o If there is no
valid address in the SROM, and a definition in the
environment exists, then the value from the
environment variable is
used.
o If both the SROM and the environment contain a MAC
address, and
both addresses are
the same, this MAC address is used.
o If both the SROM and the
environment contain a MAC address, and the
addresses differ, the value from the environment is used and
a
warning is printed.
o
If neither SROM nor the environment contain a MAC address, an error
is raised.
Image
Formats:
==============
The "boot" commands of this
monitor operate on "image" files which
can be basicly anything,
preceeded by a special header; see the
definitions in include/image.h for
details; basicly, the header
defines the following image properties:
*
Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4.4BSD, Linux, SVR4, Esix, Solaris, Irix,
SCO, Dell, NCR, VxWorks,
LynxOS,
pSOS, QNX, RTEMS, ARTOS;
Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS,
LynxOS).
* Target CPU Architecture (Provisions for Alpha, ARM, Intel
x86,
IA64, MIPS, NIOS, PowerPC,
IBM S390, SuperH, Sparc, Sparc 64 Bit;
Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
*
Compression Type (uncompressed, gzip, bzip2)
* Load Address
* Entry
Point
* Image Name
* Image Timestamp
The header is marked
by a special Magic Number, and both the header
and the data portions of
the image are secured against corruption by
CRC32 checksums.
Linux
Support:
==============
Although U-Boot should support any OS
or standalone application
easily, the main focus has always been on Linux
during the design of
U-Boot.
U-Boot includes many features that
so far have been part of some
special "boot loader" code within
the Linux kernel. Also, any
"initrd" images to be used are no
longer part of one big Linux image;
instead, kernel and "initrd"
are separate images. This implementation
serves several purposes:
-
the same features can be used for other OS or standalone
applications (for instance: using compressed
images to reduce the
Flash memory
footprint)
- it becomes much easier to port new Linux kernel
versions because
lots of
low-level, hardware dependent stuff are done by U-Boot
- the same
Linux kernel image can now be used with different "initrd"
images; of course this also means that
different kernel images can
be
run with the same "initrd". This makes testing easier (you
don't
have to build a new
"zImage.initrd" Linux image when you just
change a file in your "initrd").
Also, a field-upgrade of the
software is easier now.
Linux HOWTO:
============
Porting
Linux to U-Boot based systems:
---------------------------------------
U-Boot
cannot save you from doing all the necessary modifications to
configure
the Linux device drivers for use with your target hardware
(no, we don't
intend to provide a full virtual machine interface to
Linux :-).
But
now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
Just
make sure your machine specific header file (for instance
include/asm-ppc/tqm8xx.h)
includes the same definition of the Board
Information structure as we
define in include/u-boot.h, and make
sure that your definition of
IMAP_ADDR uses the same value as your
U-Boot configuration in CFG_IMMR.
Configuring
the Linux kernel:
-----------------------------
No specific
requirements for U-Boot. Make sure you have some root
device (initial
ramdisk, NFS) for your target system.
Building a Linux
Image:
-----------------------
With U-Boot, "normal"
build targets like "zImage" or "bzImage" are
not used.
If you use recent kernel source, a new build target
"uImage"
will exist which automatically builds an image usable by
U-Boot. Most
older kernels also have support for a "pImage" target,
which was
introduced for our predecessor project PPCBoot and uses a
100% compatible
format.
Example:
make
TQM850L_config
make
oldconfig
make dep
make uImage
The
"uImage" build target uses a special tool (in 'tools/mkimage')
to
encapsulate a compressed Linux kernel image with header information,
CRC32 checksum etc. for
use with U-Boot. This is what we are doing:
* build a standard
"vmlinux" kernel image (in ELF binary format):
* convert
the kernel into a raw binary image:
${CROSS_COMPILE}-objcopy
-O binary \
-R .note -R .comment \
-S vmlinux linux.bin
* compress
the binary image:
gzip -9
linux.bin
* package compressed binary image for U-Boot:
mkimage -A ppc -O linux -T kernel -C gzip
\
-a 0 -e 0 -n
"Linux Kernel Image" \
-d
linux.bin.gz uImage
The "mkimage" tool can also be
used to create ramdisk images for use
with U-Boot, either separated from
the Linux kernel image, or
combined into one file. "mkimage"
encapsulates the images with a 64
byte header containing information about
target architecture,
operating system, image type, compression method,
entry points, time
stamp, CRC32 checksums, etc.
"mkimage"
can be called in two ways: to verify existing images and
print the header
information, or to build new images.
In the first form (with "-l"
option) mkimage lists the information
contained in the header of an
existing U-Boot image; this includes
checksum verification:
tools/mkimage -l image
-l ==> list image header information
The second form (with
"-d" option) is used to build a U-Boot image
from a "data
file" which is used as image payload:
tools/mkimage -A arch -O os -T type -C comp -a addr -e ep
\
-n name -d data_file image
-A ==> set architecture to 'arch'
-O ==> set
operating system to 'os'
-T ==> set image type to 'type'
-C ==> set compression type 'comp'
-a ==> set load
address to 'addr' (hex)
-e ==> set entry point to 'ep'
(hex)
-n ==> set image name to 'name'
-d ==> use image data from 'datafile'
Right now, all Linux
kernels for PowerPC systems use the same load
address (0x00000000), but
the entry point address depends on the
kernel version:
- 2.2.x
kernels have the entry point at 0x0000000C,
- 2.3.x and later kernels have
the entry point at 0x00000000.
So a typical call to build a U-Boot
image would read:
->
tools/mkimage -n '2.4.4 kernel for TQM850L' \
> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
> -d
/opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
> examples/uImage.TQM850L
Image Name: 2.4.4 kernel for TQM850L
Created: Wed Jul 19 02:34:59 2000
Image Type: PowerPC Linux Kernel Image (gzip compressed)
Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
Load Address: 0x00000000
Entry
Point: 0x00000000
To verify
the contents of the image (or check for corruption):
-> tools/mkimage -l
examples/uImage.TQM850L
Image
Name: 2.4.4 kernel for TQM850L
Created: Wed Jul 19 02:34:59 2000
Image Type: PowerPC
Linux Kernel Image (gzip compressed)
Data
Size: 335725 Bytes = 327.86 kB = 0.32
MB
Load Address:
0x00000000
Entry Point: 0x00000000
NOTE: for embedded
systems where boot time is critical you can trade
speed for memory and
install an UNCOMPRESSED image instead: this
needs more space in Flash, but
boots much faster since it does not
need to be uncompressed:
-> gunzip
/opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
-> tools/mkimage -n '2.4.4 kernel for
TQM850L' \
> -A ppc -O linux
-T kernel -C none -a 0 -e 0 \
>
-d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
>
examples/uImage.TQM850L-uncompressed
Image
Name: 2.4.4 kernel for TQM850L
Created: Wed Jul 19 02:34:59 2000
Image Type: PowerPC
Linux Kernel Image (uncompressed)
Data
Size: 792160 Bytes = 773.59 kB = 0.76
MB
Load Address: 0x00000000
Entry Point: 0x00000000
Similar you can build U-Boot images
from a 'ramdisk.image.gz' file
when your kernel is intended to use an
initial ramdisk:
->
tools/mkimage -n 'Simple Ramdisk Image' \
>
-A ppc -O linux -T ramdisk -C gzip \
>
-d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
Image Name: Simple Ramdisk Image
Created: Wed Jan 12 14:01:50 2000
Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
Load Address: 0x00000000
Entry
Point: 0x00000000
Installing
a Linux Image:
-------------------------
To downloading a
U-Boot image over the serial (console) interface,
you must convert the
image to S-Record format:
objcopy
-I binary -O srec examples/image examples/image.srec
The 'objcopy'
does not understand the information in the U-Boot
image header, so the
resulting S-Record file will be relative to
address 0x00000000. To load it
to a given address, you need to
specify the target address as 'offset'
parameter with the 'loads'
command.
Example: install the image
to address 0x40100000 (which on the
TQM8xxL is in the first Flash
bank):
=> erase
40100000 401FFFFF
..........
done
Erased 8 sectors
=> loads 40100000
## Ready for S-Record download ...
~>examples/image.srec
1 2 3 4 5 6 7 8 9 10 11 12 13 ...
...
15989
15990 15991 15992
[file
transfer complete]
[connected]
## Start Addr = 0x00000000
You
can check the success of the download using the 'iminfo' command;
this
includes a checksum verification so you
can be sure no data
corruption happened:
=> imi 40100000
## Checking Image at 40100000 ...
Image Name: 2.2.13 for initrd
on TQM850L
Image Type:
PowerPC Linux Kernel Image (gzip compressed)
Data Size: 335725 Bytes = 327 kB = 0 MB
Load Address: 00000000
Entry Point: 0000000c
Verifying Checksum ... OK
Boot
Linux:
-----------
The "bootm" command is used to
boot an application that is stored in
memory (RAM or Flash). In case of a
Linux kernel image, the contents
of the "bootargs" environment
variable is passed to the kernel as
parameters. You can check and modify
this variable using the
"printenv" and "setenv"
commands:
=>
printenv bootargs
bootargs=root=/dev/ram
=> setenv bootargs root=/dev/nfs rw
nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
=> printenv bootargs
bootargs=root=/dev/nfs rw
nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
=> bootm 40020000
## Booting Linux kernel at 40020000
...
Image Name: 2.2.13 for
NFS on TQM850L
Image Type:
PowerPC Linux Kernel Image (gzip compressed)
Data Size: 381681 Bytes = 372 kB = 0 MB
Load Address: 00000000
Entry Point: 0000000c
Verifying Checksum ... OK
Uncompressing Kernel Image ... OK
Linux
version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1
Wed Jul 19 02:35:17 MEST 2000
Boot
arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC
nfsaddrs=10.0.0.99:10.0.0.2
time_init:
decrementer frequency = 187500000/60
Calibrating
delay loop... 49.77 BogoMIPS
Memory:
15208k available (700k kernel code, 444k data, 32k init)
[c0000000,c1000000]
...
If
you want to boot a Linux kernel with initial ram disk, you pass
the memory
addresses of both the kernel and the initrd image (PPBCOOT
format!) to the
"bootm" command:
=>
imi 40100000 40200000
##
Checking Image at 40100000 ...
Image Name:
2.2.13 for initrd on TQM850L
Image Type:
PowerPC Linux Kernel Image (gzip compressed)
Data Size: 335725 Bytes = 327 kB = 0 MB
Load Address: 00000000
Entry Point: 0000000c
Verifying Checksum ... OK
## Checking Image at 40200000 ...
Image Name: Simple Ramdisk
Image
Image Type:
PowerPC Linux RAMDisk Image (gzip compressed)
Data Size: 566530 Bytes = 553 kB = 0 MB
Load Address: 00000000
Entry Point: 00000000
Verifying Checksum ... OK
=> bootm 40100000 40200000
## Booting Linux kernel at 40100000
...
Image Name: 2.2.13 for
initrd on TQM850L
Image Type:
PowerPC Linux Kernel Image (gzip compressed)
Data Size: 335725 Bytes = 327 kB = 0 MB
Load Address: 00000000
Entry Point: 0000000c
Verifying Checksum ... OK
Uncompressing Kernel Image ... OK
##
Loading RAMDisk Image at 40200000 ...
Image Name:
Simple Ramdisk Image
Image Type:
PowerPC Linux RAMDisk Image (gzip compressed)
Data Size: 566530 Bytes = 553 kB = 0 MB
Load Address: 00000000
Entry Point: 00000000
Verifying Checksum ... OK
Loading Ramdisk ... OK
Linux
version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1
Wed Jul 19 02:32:08 MEST 2000
Boot
arguments: root=/dev/ram
time_init:
decrementer frequency = 187500000/60
Calibrating
delay loop... 49.77 BogoMIPS
...
RAMDISK: Compressed image found at block
0
VFS: Mounted root (ext2
filesystem).
bash#
More
About U-Boot Image Types:
------------------------------
U-Boot
supports the following image types:
"Standalone Programs" are directly runnable in the
environment
provided by U-Boot;
it is expected that (if they behave
well)
you can continue to work in U-Boot after return from
the Standalone Program.
"OS Kernel Images" are usually
images of some Embedded OS which
will
take over control completely. Usually these programs
will install their own set of exception
handlers, device
drivers, set
up the MMU, etc. - this means, that you cannot
expect to re-enter U-Boot except by resetting the CPU.
"RAMDisk Images" are more or less
just data blocks, and their
parameters
(address, size) are passed to an OS kernel that is
being started.
"Multi-File Images" contain several images, typically an
OS
(Linux) kernel image and one
or more data images like
RAMDisks.
This construct is useful for instance when you want
to boot over the network using BOOTP etc.,
where the boot
server provides
just a single image file, but you want to get
for instance an OS kernel and a RAMDisk image.
"Multi-File Images" start with a
list of image sizes, each
image
size (in bytes) specified by an "uint32_t" in network
byte order. This list is terminated by an
"(uint32_t)0".
Immediately
after the terminating 0 follow the images, one by
one, all aligned on "uint32_t" boundaries (size
rounded up to
a multiple of 4
bytes).
"Firmware
Images" are binary images containing firmware (like
U-Boot or FPGA images) which usually will
be programmed to
flash
memory.
"Script
files" are command sequences that will be executed by
U-Boot's command interpreter; this feature
is especially
useful when you
configure U-Boot to use a real shell (hush)
as command interpreter.
Standalone
HOWTO:
=================
One of the features of U-Boot is that
you can dynamically load and
run "standalone" applications,
which can use some resources of
U-Boot like console I/O functions or
interrupt services.
Two simple examples are included with the
sources:
"Hello World" Demo:
-------------------
'examples/hello_world.c'
contains a small "Hello World" Demo
application; it is
automatically compiled when you build U-Boot.
It's configured to run at
address 0x00040004, so you can play with it
like that:
=> loads
## Ready for S-Record download ...
~>examples/hello_world.srec
1 2 3 4 5 6 7 8 9 10 11 ...
[file transfer complete]
[connected]
## Start Addr = 0x00040004
=> go 40004 Hello World! This is a
test.
## Starting application
at 0x00040004 ...
Hello
World
argc = 7
argv[0] = "40004"
argv[1] = "Hello"
argv[2] = "World!"
argv[3] = "This"
argv[4] = "is"
argv[5] = "a"
argv[6] = "test."
argv[7] = "<NULL>"
Hit any key to exit ...
## Application terminated, rc = 0x0
Another
example, which demonstrates how to register a CPM interrupt
handler with
the U-Boot code, can be found in 'examples/timer.c'.
Here, a CPM timer is
set up to generate an interrupt every second.
The interrupt service
routine is trivial, just printing a '.'
character, but this is just a demo
program. The application can be
controlled by the following keys:
? - print current values og the CPM Timer
registers
b - enable interrupts
and start timer
e - stop timer
and disable interrupts
q - quit
application
=>
loads
## Ready for S-Record
download ...
~>examples/timer.srec
1 2 3 4 5 6 7 8 9 10 11 ...
[file transfer complete]
[connected]
## Start Addr = 0x00040004
=> go 40004
##
Starting application at 0x00040004 ...
TIMERS=0xfff00980
Using timer 1
tgcr @ 0xfff00980, tmr
@ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @
0xfff009b0
Hit 'b':
[q,
b, e, ?] Set interval 1000000 us
Enabling
timer
Hit '?':
[q, b, e,
?] ........
tgcr=0x1,
tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
Hit '?':
[q, b, e, ?] .
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0,
tcn=0x2ad4, ter=0x0
Hit '?':
[q,
b, e, ?] .
tgcr=0x1,
tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
Hit '?':
[q, b, e, ?] .
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0,
tcn=0x169d, ter=0x0
Hit 'e':
[q,
b, e, ?] ...Stopping timer
Hit 'q':
[q,
b, e, ?] ## Application terminated, rc = 0x0
Minicom
warning:
================
Over time, many people have reported
problems when trying to use the
"minicom" terminal emulation
program for serial download. I (wd)
consider minicom to be broken, and
recommend not to use it. Under
Unix, I recommend to use C-Kermit for
general purpose use (and
especially for kermit binary protocol download
("loadb" command), and
use "cu" for S-Record download
("loads" command).
Nevertheless, if you absolutely want to
use it try adding this
configuration to your "File transfer
protocols" section:
Name Program Name
U/D FullScr IO-Red. Multi
X kermit
/usr/bin/kermit -i -l %l -s
Y U Y N N
Y kermit
/usr/bin/kermit -i -l %l -r
N D Y N N
NetBSD Notes:
=============
Starting
at version 0.9.2, U-Boot supports NetBSD both as host
(build U-Boot) and
target system (boots NetBSD/mpc8xx).
Building requires a cross
environment; it is known to work on
NetBSD/i386 with the
cross-powerpc-netbsd-1.3 package (you will also
need gmake since the
Makefiles are not compatible with BSD make).
Note that the cross-powerpc
package does not install include files;
attempting to build U-Boot will
fail because <machine/ansi.h> is
missing. This file has to be installed and patched manually:
# cd
/usr/pkg/cross/powerpc-netbsd/include
#
mkdir powerpc
# ln -s powerpc
machine
# cp
/usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
# ${EDIT} powerpc/ansi.h ## must remove __va_list,
_BSD_VA_LIST
Native builds *don't* work due to incompatibilities
between native
and U-Boot include files.
Booting assumes that
(the first part of) the image booted is a
stage-2 loader which in turn
loads and then invokes the kernel
proper. Loader sources will eventually
appear in the NetBSD source
tree (probably in
sys/arc/mpc8xx/stand/u-boot_stage2/); in the
meantime, send mail to
bruno@exet-ag.de and/or wd@denx.de for
details.
Implementation
Internals:
=========================
The following is not
intended to be a complete description of every
implementation detail.
However, it should help to understand the
inner workings of U-Boot and
make it easier to port it to custom
hardware.
Initial
Stack, Global Data:
---------------------------
The
implementation of U-Boot is complicated by the fact that U-Boot
starts
running out of ROM (flash memory), usually without access to
system RAM
(because the memory controller is not initialized yet).
This means that we
don't have writable Data or BSS segments, and BSS
is not initialized as
zero. To be able to get a C environment working
at all, we have to
allocate at least a minimal stack. Implementation
options for this are
defined and restricted by the CPU used: Some CPU
models provide on-chip
memory (like the IMMR area on MPC8xx and
MPC826x processors), on others
(parts of) the data cache can be
locked as (mis-) used as memory,
etc.
Chris Hallinan
posted a good summary of these issues to the
u-boot-users
mailing list:
Subject:
RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
From: "Chris Hallinan"
<clh@net1plus.com>
Date:
Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
...
Correct
me if I'm wrong, folks, but the way I understand it
is this: Using DCACHE as initial RAM for
Stack, etc, does not
require
any physical RAM backing up the cache. The cleverness
is that the cache is being used as a
temporary supply of
necessary
storage before the SDRAM controller is setup. It's
beyond the scope of this list to expain the details, but
you
can see how this works by
studying the cache architecture and
operation
in the architecture and processor-specific manuals.
OCM is On Chip Memory, which I believe the
405GP has 4K. It
is another
option for the system designer to use as an
initial stack/ram area prior to SDRAM being available.
Either
option should work for
you. Using CS 4 should be fine if your
board
designers haven't used it for something that would
cause you grief during the initial boot! It is frequently
not
used.
CFG_INIT_RAM_ADDR should be somewhere that
won't interfere
with your
processor/board/system design. The default value
you will find in any recent u-boot distribution in
Walnut405.h should work for you. I'd set
it to a value larger
than your
SDRAM module. If you have a 64MB SDRAM module, set
it above 400_0000. Just make sure your board has no
resources
that are supposed to
respond to that address! That code in
start.S
has been around a while and should work as is when
you get the config right.
-Chris Hallinan
DS4.COM,
Inc.
It is essential to remember this, since it has some impact on
the C
code for the initialization procedures:
* Initialized
global data (data segment) is read-only. Do not attempt
to write it.
* Do not use any
unitialized global data (or implicitely initialized
as zero data - BSS segment) at all - this is
undefined, initiali-
zation is
performed later (when relocating to RAM).
* Stack space is very
limited. Avoid big data buffers or things like
that.
Having only the stack as writable memory limits
means we cannot use
normal global data to share information beween the
code. But it
turned out that the implementation of U-Boot can be
greatly
simplified by making a global data structure (gd_t) available to
all
functions. We could pass a pointer to this data as argument to
_all_
functions, but this would bloat the code. Instead we use a feature
of
the GCC compiler (Global Register Variables) to share the data:
we
place a pointer (gd) to the global data into a register which we
reserve
for this purpose.
When choosing a register for such a purpose we are
restricted by the
relevant
(E)ABI specifications for the
current architecture, and by
GCC's implementation.
For PowerPC,
the following registers have specific use:
R1: stack pointer
R2: TOC
pointer
R3-R4: parameter passing and return values
R5-R10: parameter passing
R13: small
data area pointer
R30: GOT pointer
R31: frame pointer
(U-Boot also uses R14 as internal GOT
pointer.)
==> U-Boot
will use R29 to hold a pointer to the global data
Note: on PPC, we could use a static
initializer (since the
address
of the global data structure is known at compile time),
but it turned out that reserving a register
results in somewhat
smaller
code - although the code savings are not that big (on
average for all boards 752 bytes for the
whole U-Boot image,
624 text +
127 data).
On ARM, the following registers are used:
R0: function
argument word/integer result
R1-R3: function argument word
R9: GOT
pointer
R10: stack limit (used only if stack checking if
enabled)
R11: argument (frame) pointer
R12: temporary
workspace
R13: stack pointer
R14: link register
R15: program
counter
==> U-Boot will
use R8 to hold a pointer to the global data
Memory
Management:
------------------
U-Boot runs in system state and
uses physical addresses, i.e. the
MMU is not used either for address
mapping nor for memory protection.
The available memory is mapped to
fixed addresses using the memory
controller. In this process, a contiguous
block is formed for each
memory type (Flash, SDRAM, SRAM), even when it
consists of several
physical memory banks.
U-Boot is installed
in the first 128 kB of the first Flash bank (on
TQM8xxL modules this is
the range 0x40000000 ... 0x4001FFFF). After
booting and sizing and
initializing DRAM, the code relocates itself
to the upper end of DRAM.
Immediately below the U-Boot code some
memory is reserved for use by
malloc() [see CFG_MALLOC_LEN
configuration setting]. Below that, a
structure with global Board
Info data is placed, followed by the stack
(growing downward).
Additionally, some exception handler code is
copied to the low 8 kB
of DRAM (0x00000000 ... 0x00001FFF).
So
a typical memory configuration with 16 MB of DRAM could look like
this:
0x0000 0000 Exception Vector code
:
0x0000
1FFF
0x0000 2000 Free for Application Use
:
:
:
:
0x00FB FF20 Monitor Stack (Growing downward)
0x00FB FFAC Board Info Data and permanent copy of global data
0x00FC 0000 Malloc Arena
:
0x00FD
FFFF
0x00FE 0000 RAM Copy of Monitor Code
... eventually:
LCD or video framebuffer
... eventually: pRAM (Protected RAM -
unchanged by reset)
0x00FF FFFF [End of RAM]
System
Initialization:
----------------------
In the reset
configuration, U-Boot starts at the reset entry point
(on most PowerPC
systens at address 0x00000100). Because of the reset
configuration for
CS0# this is a mirror of the onboard Flash memory.
To be able to re-map
memory U-Boot then jumps to its link address.
To be able to implement the
initialization code in C, a (small!)
initial stack is set up in the
internal Dual Ported RAM (in case CPUs
which provide such a feature like
MPC8xx or MPC8260), or in a locked
part of the data cache. After that,
U-Boot initializes the CPU core,
the caches and the SIU.
Next,
all (potentially) available memory banks are mapped using a
preliminary
mapping. For example, we put them on 512 MB boundaries
(multiples of
0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
on 0x40000000 and
0x60000000, SRAM on 0x80000000). Then UPM A is
programmed for SDRAM
access. Using the temporary configuration, a
simple memory test is run
that determines the size of the SDRAM
banks.
When there is more
than one SDRAM bank, and the banks are of
different size, the largest is
mapped first. For equal size, the first
bank (CS2#) is mapped first. The
first mapping is always for address
0x00000000, with any additional banks
following immediately to create
contiguous memory starting from 0.
Then,
the monitor installs itself at the upper end of the SDRAM area
and
allocates memory for use by malloc() and for the global Board
Info data;
also, the exception vector code is copied to the low RAM
pages, and the
final stack is set up.
Only after this relocation will you have a
"normal" C environment;
until that you are restricted in several
ways, mostly because you are
running from ROM, and because the code will
have to be relocated to a
new address in RAM.
U-Boot
Porting Guide:
----------------------
[Based on messages by
Jerry Van Baren in the U-Boot-Users mailing
list, October 2002]
int
main (int argc, char *argv[])
{
sighandler_t
no_more_time;
signal
(SIGALRM, no_more_time);
alarm
(PROJECT_DEADLINE - toSec (3 * WEEK));
if (available_money > available_manpower) {
pay consultant to port U-Boot;
return 0;
}
Download latest U-Boot source;
Subscribe to u-boot-users mailing
list;
if (clueless)
{
email ("Hi, I am
new to U-Boot, how do I get started?");
}
while
(learning) {
Read the
README file in the top level directory;
Read
http://www.denx.de/twiki/bin/view/DULG/Manual ;
Read the source, Luke;
}
if
(available_money > toLocalCurrency ($2500)) {
Buy a BDI2000;
}
else {
Add a lot of
aggravation and time;
}
Create your own board support
subdirectory;
Create your
own board config file;
while
(!running) {
do {
Add / modify source
code;
} until
(compiles);
Debug;
if (clueless)
email ("Hi, I am having
problems...");
}
Send patch file to Wolfgang;
return 0;
}
void
no_more_time (int sig)
{
hire_a_guru();
}
Coding Standards:
-----------------
All
contributions to U-Boot should conform to the Linux kernel
coding style;
see the file "Documentation/CodingStyle" in your Linux
kernel
source directory.
Please note that U-Boot is implemented in C (and
to some small parts
in Assembler); no C++ is used, so please do not use
C++ style
comments (//) in your code.
Please also stick to the
following formatting rules:
- remove any trailing white space
- use
TAB characters for indentation, not spaces
- make sure NOT to use DOS
'\r\n' line feeds
- do not add more than 2 empty lines to source
files
- do not add trailing empty lines to source files
Submissions
which do not conform to the standards may be returned
with a request to
reformat the changes.
Submitting Patches:
-------------------
Since
the number of patches for U-Boot is growing, we need to
establish some
rules. Submissions which do not conform to these rules
may be rejected,
even when they contain important and valuable stuff.
When you
send a patch, please include the following information with
it:
*
For bug fixes: a description of the bug and how your patch fixes
this bug. Please try to include a way of
demonstrating that the
patch
actually fixes something.
* For new features: a description of the
feature and your
implementation.
* A CHANGELOG entry as plaintext (separate
from the patch)
* For major contributions, your entry to the CREDITS
file
* When you add support for a new board, don't forget to add
this
board to the MAKEALL script,
too.
* If your patch adds new configuration options, don't forget
to
document these in the README
file.
* The patch itself. If you are accessing the CVS repository
use "cvs
update; cvs diff
-puRN"; else, use "diff -purN OLD NEW". If your
version of diff does not support these
options, then get the latest
version of GNU diff.
The current directory when running this command shall be the top
level directory of the U-Boot source tree,
or it's parent directory
(i. e.
please make sure that your patch includes sufficient
directory information for the affected
files).
We accept patches
as plain text, MIME attachments or as uuencoded
gzipped text.
* If one logical set of modifications
affects or creates several
files,
all these changes shall be submitted in a SINGLE patch file.
*
Changesets that contain different, unrelated modifications shall be
submitted as SEPARATE patches, one patch per
changeset.
Notes:
* Before sending the patch, run
the MAKEALL script on your patched
source tree and make sure that no errors or warnings are reported
for any of the boards.
* Keep
your modifications to the necessary minimum: A patch
containing several unrelated changes or
arbitrary reformats will be
returned with a request to re-formatting / split it.
* If you
modify existing code, make sure that your new code does not
add to the memory footprint of the code ;-)
Small is beautiful!
When adding
new features, these should compile conditionally only
(using #ifdef), and the resulting code with
the new feature
disabled must not
need more memory than the old code without your
modification.